my girlfriend is going to kill herself very soon...because of me

I've been in a relationship with this girl since 8 months ago, I was planning to leave country for education in six months and told her from the start.
later I found out she has serious mental problems(I think it might be Bi-polar) due to being raised by an abusive father and a failed marriage with a beating (now ex)husband. she fell in love with me and became too attached, two months ago when we said goodbye and I left country she tried to commit suicide after just 3 days. she was lucky and came out of coma after 2 days.
I came back with much difficulties to see and comfort her. but now I need to leave country again and she clearly told me shes gonna do it again because she doesn't have anyone other than me and is now loosing me and she has nothing else to lose.
I know shes serious but I need to leave or I'm not gonna be able to continue my education any time soon.
she had been on medication since she was 13 but has cut the medication since she came out of coma, she refuses any medication or counseling. has serious issues with her mother and sister whom shes living with and they're not supportive anymore.
I know I can't take the fact that someone else kills herself because of me, specially someone I loved.
she is a very sweet and caring girl, young, brilliant and beautiful. I think I'm gonna do it too if she does it. I have a weak heart(runs in my family) and I've been feeling these random pains lately.
what do I do in this situation? I wake up with guilt and sleep with guilt I can't continue living like this with the stress that any second she might do it again.