Does she know about your problems? How does she react to it?
A lot of times, I make assumptions (and yes, even crazy conspiracy thaughts) of what others are thinking/saying about me. These are usually just my mind playing tricks on me.
Talk to her and find out what her feelings are. She might feel just as helpless as you do and would just want you to get better.
I truely hope you and your girlfriend wil remain happy together. It's hard not having someone who understands and supports you.
This is a life long "problem" and medication can only do so much...It takes a strong person not to act on one's urge to kill one self...it takes even a stronger one to understand and be supportive of you through thick and thin.
Let her know how much she means to you and how much you appreciate her support and understanding. Love is the only thing in this life worth living for...