Why does Chuck McGill end the season like this?

Question

At the end of the Season 3 of Better Call Saul, Chuck McGill ends (I think) with a full win situation and obtains everything he wants:

• He manages to extort a huge severance payout ($3 million) from Howard Hamlin, even Howard says "You won".

• He manages to finally discard his brother by telling him the truth, "you've never mattered all that much to me".

• He is recovering from his illness about believing he is a Electromagnetic Hypersensitive (EHS).

However,

he deliberately commits suicide by kicking his lantern and setting his house on fire.

Answer 1

He was looking for a way out...

NYTimes.com interview with Michael McKean

Monday’s Season 3 finale brought a fatal relapse, as Chuck broke with both his law firm and his brother. He then tore apart his house in search of the unfindable irritant fueling what Michael McKean, the actor who plays him, described as Chuck’s “unscratchable itch.”

McKean: “Searching for that source was a very active thing,” he said. “It was a man looking for a way out, and he had to settle for that way out.”

NYT: What do you think finally drove Chuck over the edge?

McKean: "Part of it was the desire to have this behind him, and the fact that no matter how many times they shut off the power, that there was something going on in the house, or at least in his mind. It was still that unscratchable itch. He thought maybe this all goes away if I build this Mylar man cave, but no. Listen, he’s a man whose mind isn’t working right."

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He manages to finally discard his brother away by telling him the truth, "you've never mattered all that much to me".

Actually, it's a lie

Forbes: When Chuck is telling Jimmy “You never mattered to me” did you mean to play that with that sense of finality. It seems Jimmy almost shrugs it off as just another in a long line of Chuck's insults.

McKean: There was definitely an element of goodbye. The cotter pin of that moment is the lie: that you don’t mean much to me.

[continued] It’s not all positive. It’s not something that Chuck can even express any other way. But when he says, “You never meant that much to me” It’s clearly a lie. Jimmy has been at the center of so much of Chuck’s actions in the time scheme of the show. What I’m saying is as much as I can tell you.

^{Forbes.com interview also with McKean}

Answer 2

I believe the other answers are more in depth; but I wanted to add a bit of nuance to the foundation of your question.

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TL;DR

• Chuck lost his career. He loves the law (more than his own brother). This is a big personal loss for Chuck.
• Chuck's hurtful statement to Jimmy was not, in any way, a win for Chuck. It'd be more accurate to call it a necessary evil.
• Chuck's realization that his illness is imaginary also brings with it a burden of guilt, because of everything that Jimmy has done for Chuck during his perceived illness.

Loss of livelihood, loss of his only living family, immense ammounts of self-blame and guilt. This is a recipe for suicide. To his mind, Chuck has nothing to live for.

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He manages to extort a huge amount of severance pay ($3 millions) from Howard Hamlin, even Howard says "You won".

Pedantic comment: Chuck wins 8 million. He suggested that his 1/3 share of HHM amounts to around 8 million. When Howard gives Chuck the check for 3 million, he also mentions that it is the first of three checks. it stands to reason that Howard is paying Chuck the 8 million of his share, in three separate payments.

Hamlin's statement was closer to "I give up" than telling Chuck he wins.

Furthermore, Chuck didn't actually win. You can clearly read Chuck's intentions from the list of possible outcomes that he mentions to the board:

1. I will sue you and I will ruin HHM's reputation (which will endanger the company's future)
2. I will get my share (which will drive HHM into bankrupcy and endanger it's future)
3. Let's just forget this all happened and let's be friends again.

Chuck's message is very simple: If I go down, so does HHM. Make your choice.

Chuck presents option 1 and 2 not because he wants it, but because they are deterrents. Chuck doesn't want to get pushed out, he wants to keep practicing law at HHM. If Chuck truly wanted option 1 or 2, then there is no reason for him to suggest option 3, which is a much nicer and softer option by comparison.
Chuck is manipulating HHM. He knows they cannot choose option 1 or 2 because no one wants the company to close. He is trying to force the board's hand to choose option 3, which is what Chuck really wants.

But Howard is not an idiot. He knows that's what Chuck wants. So he finds a way to make option 2 (paying Chuck) possible, which catches Chuck by surprise.
Howard saying "you win" was a facetious statement. Chuck was pretending that he wanted a payout; and Howard facetiously plays along with Chuck's lie and therefore states that Chuck "wins" (i.e. Chuck gets the thing that he claims he wants).

This is further proven by Howard's public farewell to Chuck. You can see how much Chuck does not want this to happen (but he takes it in stride, to not lose face). Howard makes Chuck's retirement public, so that it can never be taken back. Howard basically salted the earth, making option 3 impossible (or at least incredibly unlikely) to ever happen.

Chuck lost. He lost the career he loves (and remember that he loves the law more than his own brother, so this is a big loss for Chuck).

He manages to finally discard his brother away by telling him the truth, "you've never mattered all that much to me".

I don't like Chuck as a brother to Jimmy. I really, really hate him. He's cold, manipulative, selfish, and has a neverending supply of arrrogance to him.
However, I do think that his statement to Jimmy is a lie; or at the very least an overstatement.

There are a few reasons for Chuck to lie about this:

• It's an emotional overstatement because Chuck is upset. This could be due to Jimmy, or due to an external factor like losing his job.
• It's meant to hurt Jimmy; because Chuck feels that the war between him and Jimmy is not over yet.
• It's meant to make Jimmy go away; because Chuck does not want to associate with Jimmy anymore.

There is one other (bittersweet) possibility though:

• Chuck intentionally paints himself as the bad guy; so that Jimmy won't feel guilty (after Chuck's suicide) about not making amends (before Chuck's suicide).

It's the classic tale of wanting to break up with a girl. If you let her down gently ("it's not you, it's me" or "I just don't think I'm ready"); then you allow for the possibility that she still loves you after you break up, and it will negatively affect her life (not moving on, being unhappy, trying to give you a second chance, ...).
However, if you let her see you as the villain (e.g. "I never loved you anyway" or "I'm in love with someone better"), then she will not cherish any hope about a second chance (nor will she want to give you a second chance), which means that she blames you for the failed relationship; but at least she moves on with her life.

Without a clear villain, people can resort to blaming themselves. But when there's a villain, the blame clearly lies with the villain.

I think this fits Chuck's character well.

• It's manipulative, which is Chuck's favorite approach.
• Although the initial statement will hurt Jimmy, it will be less excruciating than what Jimmy will go through if Chuck kills himself while Jimmy still hopes to make amends with Chuck. That's a very pragmatic (and unemotional) approach, which again is what Chuck tends to favor.
• Jimmy was there to make amends between him and Chuck. If Chuck's suicide was already set in stone, then it would be cruel to make Jimmy think that him and Chuck will be friends again; only to then kill himself and destroy Jimmy emotionally. In a weird sense, Chuck's hurtful statement hurts Jimmy less.

He is recovering from his illness about believing he is EHS.

Chuck's illness is a big part of his life story (as related to BCS). So let me try to be short in painting the scene:

• Chuck's illness is imaginary.
• Chuck truly experiences the illness.
• Even when contemplating that it is in his head (which is what he does after Jimmy's hearing when he carried the battery); Chuck still experiences it. To the best of his cognitive abilities, he can't avoid suffering from his imaginary illness.

Although Chuck has been selfish and preoccupied with himself for most of the show; he shows some humanity when he discusses his illness with the doctor. When discussing the possibility of his illness being in his head; Chuck realizes what that means about how he has behaved himself (especially towards Jimmy).

From the script, emphasis mine:

Doctor: [Inhales sharply, clears throat] What made it so important to talk to me that night?

Chuck: [Sighs] I'd had an incident. A very public incident. Perhaps the worst experience of my life.
It was proven to me, in public, and beyond the shadow of a doubt, that there was a battery, a fully charged battery, almost next to my skin for the better part of two hours. And I felt nothing.

Doctor: What does that mean to you?

Chuck: This condition to me, it's as real as that chair. It's as real as this house. It's as real as you.
But what if it's not? What if it's all in my head? And if that's true, if it's not real, then what have I done? [My addition: Chuck gets exceptionally emotional at the thought of this]

Although he has not conclusively proven this yet; assuming Chuck's illness is imaginary, Chuck is starting to realize what he has put Jimmy through.

In the past, he was okay with asking for Jimmy's help, to the point where Jimmy was pretty much Chuck's caretaker; because Chuck had no other options, he was sick and incapable of helping himself.
But if Chuck acknowledges that his illness is self-invented; that also means that he has no justification for what he asked of Jimmy (while still being kind of a dick to Jimmy at the same time).

You are right that Chuck is starting to realize that his illness is imagined. However, with that realization also comes the burden of guilt for what he has put Jimmy through, for something that turns out to be fake.

This guilt only adds to Chuck's feeling of helplessness.

Answer 3

T.S. Eliot would surely have called him a "broken Coriolanus" [See The Wasteland, "What the Thunder Said"]

This article breaks it down quite nicely, but here are the key point is "Coriolanus ... is so harsh and unyielding that he manages to get himself banished from Rome."

• Coriolanus was an exceptional general, and these qualities served him well on the battlefield, but in the political arena, which requires a different temperament, his inflexibility becomes his undoing.

• This is the case with Chuck, whom Howard repeatedly refers to as one of the greatest legal minds he's ever encountered, and yet it is Howard, willing to bend, that prevails outside the courtroom.

Yes Chuck wins, but it is a pyrrhic victory, in that the cost was greater than what was gained. At the end of Season 3, Chuck has lost everything that matters to him, which is status and the ability to practice law.

Technically, Chuck could still practice, but his reputation has been irreparably damaged per his unwillingness to let go of the Mesa Verde incident. (Chuck's prosecution of Jimmy backfires in that Chuck himself becomes the collateral damage. The raising of the malpractice rates is not insignificant, and it's unclear if solo practice would even be tenable.)

Chuck claims not to care about human relationships, but as McKean notes in the behind-the-scenes, this cannot possibly be true. Chuck has alienated the three people he had relationships with: Rebecca, Jimmy, and finally Howard.

Although on the road to recovery from his mental illness, Chuck has a severe relapse prior to kicking the lantern. (This outcome was foreshadowed by his doctor, urging him to temper his expectations, but to do so is against Chuck's nature. He can't even compromise in that regard, and thus the backlash of the relapse is that much more severe.)

Finally, regarding the $3 million, it is meaningless to Chuck. He thought the $9 million would serve only as leverage to keep him in the firm. It had to have upended his world that Howard "chewed off his own arm" in putting up his personal money to escape from Chuck's trap.

Chuck kicks the lantern over depression at having lost everything that was important to him, both acknowledged and unacknowledged.

Answer 4

I think, more than anything, it was the fact that he was proven wrong.

Think about it: His wife abandoned him, he had become a mentally ill recluse, and everyone, including his own parents, valued his brother more than him. The one thing that kept him going, and what drove his rivalry with Jimmy, was the idea that, no matter how much everyone was against him, he'd always be proven to have the moral high ground in the eyes of the law. In the finale, he lost this edge: He was prepared to sue HM on the grounds that they were wrong to push him into retirement, and the law would prove that he deserved to stay. When Howard bought him out of the firm, it was a huge blow to his ego, as he legally proved that he had the firm's interests in mind when Chuck didn't.

Notice the surprise on his face when Howard tells him his claim that he was betrayed is bs: Howard was the one person who seemed to remain on his side after everything, and now even he was telling Chuck he was wrong.

But the final nail in the coffin was his last meeting with Jimmy. Jimmy came to make amends, and Chuck rejected him. Now, his words about Jimmy having never mattered to him were obviously a lie, seeing as most of Chuck's actions since well before the start of the series revolved around Jimmy. But the message was clear: whether it was actually Jimmy's fault or not, nothing good had come from having him in his life. Chuck actually seemed to be doing fine until Jimmy showed up - at the very least, he was still able to keep his electricity on - but the fact that Jimmy was willing to reach his hand out to Chuck, and Chuck rejected him, was something Chuck couldn't cope with. Unlike his other confrontations with Jimmy (like after the Mesa Verde incident), he didn't have his legal career to fall back on. Chuck was truly left with nothing, no brother, no friends, and no moral superiority over anyone, and that was the end of the road for him.

Answer 5

I just want to point out that Chuck’s sickness wasn’t ‘fake’ as someone put it but just as real to him as any other sickness. All pain is in the head scientifically speaking, but knowing that doesn’t make a difference when you get kicked in the shin. The question really is what in Chuck’s life was causing the mental anguish which manifested as physical pain? I believe the answer is found in the Bible where it states that the over righteous person will cause desolation to himself (Eccl 7:16)This was the reason for Chuck’s pain and his eventual suicide, he just couldn’t admit he was wrong!