What past is Rez referring to?

Question

In A Star is Born, Jake Jack, whose wife wants him to be in her performance, was met by Rez:

Rez: Just by staying married to you, she looks like a joke. It's embarrassing. Let's be honest, we both know it's only a matter of time before that's pushed aside again for the real thing. And when that happens, I don't want her anywhere near you.

With again, it means that the marriage has been forgotten or ignored before in the past.

I saw the movie, but I can’t remember where Jack’s marriage was ignored.

What past is Rez referring to?

Answer 1

He is referring to Jakes Jack's alcoholism. In the scene in question, they are talking about Jakes Jack's return from rehab and Jake Jack is drinking a club soda, which is the "that" Rez is referring to, while Rez is alluding to a relapse, with "the real thing" being a real alcoholic beverage.

Rez: Just by staying married to you, she looks like a joke. It's embarrassing. Let's be honest, we both know it's only a matter of time before that's pushed aside again for the real thing. And when that happens, I don't want her anywhere near you.

Answer 2

Rez might pointing out to the time when Jake Jack ended up being in rehab because of his alcoholism, or the time when he peed at the stage during the Golden Globes, making her feel ashamed in front of everyone.
If not, Rez may just mean that Jake Jack would start ignoring her in the condition of being extremely drunk, not specifically the marriage, but her own self.