You're continuing to make the same mistake that I've been addressing this entire time. I'll pick into it at length, but I don't think there's anything else I can do to change your mind. That's on you to mull over.
she finally decided yes he should die
No one makes these kinds of utilitarian calculuses outright, let alone at all when it comes to most areas of their personal lives. Sure, sometimes people realize that their quality of life relies on ending a relationship because "life can't go on like this." Here's the thing, this conclusion arises for a range of reasons, from the need for self-care or recognition of incompatibility, to seriously detrimental behavior, like abuse, which includes physical violence and explicit emotional abuse--in this case, let's focus on forms of manipulation such as the threat of self-harm or tendency to sink into behaviors that are damaging to the relationship.
IF that were the case then yes, she should feel some guilt, obviously if she did all she could she'd get over it and move on, but IF this were the true circumstance then this should've looked a whole lot different.
Like I said, no one, even and especially those who ghost right out of one another's lives, without a trace or an explanation, dooms their exes or decides yes they should die. Feeling guilt is a natural component of a breakup because it represents the end of a relationship that both partners were invested in. But guilt like this is secondary to individual self-care, and, again, has absolutely no bearing when it comes to complicity in another's suicide.
Similarly, when a peer, loved one, or ex does commit suicide, it's natural to feel guilty because of the hopeless, frenzied need to look back at all of your experiences with them and desperately decipher what could have been done differently, anything at all that may've helped to prevent it. This is the kind of guilt that I can assure you the girl is reeling from and struggling to cope with right now.
First if she were dealing with this for a while, doing the most she could do SHOULD'VE ended up with this man in mental health care, not out in public near the one thing/person that is attributing to his condition.
No. Relationships don't bind you to your partner. There is nothing that prevents one from leaving their partner at any time other than their commitment to one another. Choosing not to suffocate in an abusive environment because "life can't go on like this" is perfectly appropriate regardless of whether or not one's harmful relationship serves as a crutch for given partners' emotional problems or mental disorders.
All I'm trying to make a point of is this. She turned her back. However the scenario, it wasn't him who gave up on resolving things.
So what? She was never under any obligation to continue the relationship. She had no way of knowing that he would react in this way. Breakups are messy, she was under no obligation to "resolve" anything as he would've preferred.
IF it were the culmination of a long history of dealing with suicidal tendencies, then she should've known better than to quit cold turkey like that. You ween people off of behavior like that. No one ever talked someone off a cliff by telling them "eh fuck it, I'm leaving."
Fucking hell, the whole point is that running away with imagined what-ifs is unhealthy, stranger. You are not privy to the various details that led up to the breakup. What's more, none of us can read minds, especially the girl, who, as I'm going to continue repeating, had no way of knowing that something like this would happen. For that matter, there's no good way to break up with someone who doesn't want to break up with you. A public place is usually helpful.
I could be wrong, he could've been completely unreasonable and she may have said something along these lines, but her body language spoke more loudly than anything he heard clearly or he wouldn't have lost all hope.
People's body language during breakups is supposed to be rough, it's a fucking breakup. She had no way of knowing he would react the way he did