Lets see, where do I start?

A few years ago I met a wonderful girl at work. We were always just friends. We would hang out often and talk, laugh, look for crazy stuff on the internet, etc. She had a boyfriend at the time, so I never made a move. My job transferred me to another city for a year and when I got back I found out she had broken up with her boyfriend and moved to Kansas City. I call her, and it seems we picked up right where we left off. Happy happy . I thought this was the girl for me. I could see myself happy with her forever. So I go see her for new years in KC. We hit it off wonderfully. After a few days my mind is made up. She's it. I ask her to move back to Tx with me, and we should talk about getting married! She agrees, much to my delight! Now I had known she had a couple of medical problems in the past, but had surgery. Specifically endometriosis, endocystitis. I also knew that she was unable to have children, but thought we could work around that if needed. What I didn't know is that she was also clinically depressed. As soon as she moved down here I could see a major difference. Turns out that I came along a week after she had been raped. Adding to the story she had her father sexually abuse her as a child, and had been dealing with depression her entire life. She didn't want to work anymore. She refused to eat. Hadn't left the house in a month, when she decides our relationship was over. So I buy her a ticket back to KC. A few days later she wants to come back, so I of course say yes! She gets back, everything seems ok for a couple of days. Then it's back to the same thing. She dissapeared for a couple of days about 2 months ago. I called her mother and had a long talk. I spoke to her friends, whom she hadn't spoken to in months. No one had any clues as to where she was. When I found her she had taken and entire bottle of vicodin and colonipin, plastic bag over her head. I cried for days. After a week of recovering, she promised to go to work, go outside, etc. At least pretend to have a somewhat normal life. As of the day I found her half dead, she hasn't left the house in 2 months. She refuses to bathe more than once a week. goes on eating binges, then will not eat for a week. She takes 10-15 vicodin a day to deal with pain related to her illness (i don't know if that's really it, or just taking them to get high) At this point I don't know what to do. I love the girl I first met and thought i knew all this time. I'm trying to understand. i want her to be better. She takes welbutrin twice a day, but doesn't seem to help. She says her goal this year is to not kill herself. Please help. I need her in my life, just not like this. I love her so much, I can't stand the thought of letting her go. But is that my only option? I need to have somewhat of a social life. I spend my days looking after her. I spend every penny and more getting her "medicine" What am I to do?