Anyone here who actually believes that Rick intended to kill himself is talking pure nonsense. He dropped his head on purpose. Killing himself would be pointless, and Rick is defined by his nihilism. "Access to infinite timelines precludes the necessity of attachment" - repeat that over and over. He is a "cold unfeeling ghost", he has seen things most people never dream of, been to god knows how many dimensions/realities, probably jumped reality more than once. If you think Rick would ever try to kill himself, you don't understand his character very well. That scene was very deep, for sure, but it's not a suicide attempt. It's feigned, it's like tying the noose and then sitting down. Rick doesn't want to die, he wants to live and that's his problem. For all he knows and has been through, life has lost its wonder and beauty. Through Unity and the things Morty and Summer said to him, he is reminded of what he has become. Endless indulgence through drugs, meaningless adventure, moving back with his family. Everything is a distraction from the inescapable reality that he, and no one else around him, understands: life is pointless, everything dies, and nothing matters. He would never kill himself because that would be even more pointless than getting drunk. He didn't love Unity, he's not some normal bloke with a case of heartbreak. This goes far deeper, right to the core of what Rick and Morty is about. It's the conflict between nihilism and purpose. That scene was the culmination, "fun's fun, but who needs it?". He is trapped with the knowledge that nothing matters, love is fake, and no one else is smart enough to see it. So he is lonely, he lacks purpose, but wants more than anything else to forget, and return to the old dimensions of his mind. Remember Simple Rick? It's all tied together. That cronenberg he killed... people are reading a lot into it, probably there is something significant there, but it's not him giving up because he's about kill himself. Don't you think if Rick wanted to kill himself, he would? Think about it. Why did he drink the fluid he used to unfreeze the cronenberg? Honestly the whole point of killing that thing was to convey to the audience what the machine does, so they understand the weight of it. I seriously doubt Rick actually cared about that thing. I find it hard to explain this, honestly I don't know why people have such a warped idea of what Rick is all about, but he doesn't care. He wants to, but he doesn't. Unfreezing a creature just to vaporise it is typical Rick. We're talking about a man who has killed thousands and sells weapons to assassins. It's as much a plot device as anything. One thing I could not be any more certain of is that Rick did not try to kill himself, frankly that's a rickdiculous suggestion. If you understand the core philosophy of the show, then you understand that scene. It has nothing to do with Unity, or love, or the cronenberg, or suicide. It's about Rick's struggle to find purpose in a fundamentally meaningless existence, because he's too smart to live in blissful ignorance like everyone around him. This escapade with Unity was nothing but a harsh reminder that he constantly running from the man he has become, because he misses what it felt like to be alive. He's far too smart to ever kill himself, he knows that a meaningless life is better than a meaningless death, but it doesn't make him feel any less empty inside. Even drinking that fluid was symbolic. He used to unfreeze the cronenberg... if only it could unfreeze his heart.
Honestly it baffles me how many Rick and Morty fans completely fail to notice that show is about nihilism. I mean, that is the entire central point of Rick's character. Knowing too much takes the wonder out of things, because those things are fundamentally meaningless. Love is a biochemical reaction evolved through natural selection, it doesn't mean anything, and Rick knows that. And he knows that he can never go back to the way he was before. That's the whole point of the simple rick's advert in the citadel. Rick is a person who understand everything, and so finds awe in nothing. And some part of him really wishes that weren't the case.