Hi, so I'm vary wary of you trying to diagnose your girlfriend. There is a lot we can't know and there's no way to diagnose someone from a third party account. She could have borderline personality disorder although what you've said does not sound like it to me. So far you've mentioned symptoms that are attached to numerous illnesses. You said her PMS is an indicator of her mood, that makes me wonder of she is suffering from PMDD. That is very treatable through medication. Anyhow, regardless of what is going on with her, it does sound like she has anger issues and the two of you should talk about that.

I'm also worried about you in this relationship. You say that numerous times she's abandoned you somewhere with no way of you getting home, and yet you haven't broken it off with her? I know 2 years can seem like a long time, but honestly, time can fly by in a relationship. I wouldn't hold on to something bad just because you are afraid there won't be someone else out there for you.

In the end, you cannot control her or how she responds to things, you can only control how you will respond to things. Putting boundaries in place is a great idea. Just remember, boundaries are for you, not for her. Boundaries are about what you will do when she steps out of line, they aren't rules for her to follow. For example, when my mother starts bad mouthing my father, I leave the room. The boundary is I won't listen to that stuff or be around it. The boundary is not: you can't talk badly about my father. Now she has to learn that if she wants my company, she can't badmouth my father. So if your boundary is about her anger, it's about what you do in response to her anger. So if she leaves you somewhere and abandons you, you won't come over to see her unless it's to discuss her behavior or until she apologizes. If she's on the warpath, you will leave until she is calm enough to discuss things. By setting boundaries like this she will learn she can't have your company unless she behaves. But it's not a rule you place on her. Otherwise you're just setting rules, and should call them such. Boundaries are what we place on ourselves as people as what we will accept and not accept.