At least half of my advice goes to men, so you’re not alone here!
But I’m very concerned that you say you want to kill yourself as a result of your feelings from fighting with your girlfriend. You may love her very much, but that doesn’t mean you have the tools to help her — she sounds like she’s been through quite a lot in her life. Loving people is easy. Being compatible is not.
She sounds like she has serious abandonment issues and probably a slew of other issues due to the history she has told you about. It sounds like there may be more you don’t know about just yet, as well.
Remember what relationships can be if you let them: supportive, loving, intimate, sexual, fun, romantic and future oriented. It doesn’t sound like that’s what you have here.
My advice is not to dive in here. She may not be the one for you if you both end up depressed to such extremes. If you can see her casually, then I’d advise proceeding, but I don’t think this is a healthy relationship as it stands now, and you both seem to need more space from each other than you have right now.
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