My friend is a WH*RE! What should I do? 10 points?

So I have this 18 year old friend who is a real WH*RE! I tried so hard to be her friend but she betrayed me everytime I gave her chance after chance. I never judged her because I was her friend. Her name is Adrian and now a lesbian. She is also a member up here http://malaysia.answers.yahoo.com/activity?show=AAkxB73laa. I don't know. All I was a true friend to her and she turned on me for no reason. She also has a problem. She has sex with everyone she comes in contact with. We talked about it but she just laughed it off. She has no respect for herself or anyone else. But how can I help her? She makes herself feel better when she has sex from one person to the next constantly. I tried to be there for her...but everytime I'm there..I get f*cked over and over. I know I should let God handle it and just pray on it. Even her own mom is ashamed of her.