I need advice...

If the two of you have drifted apart it's gonna be difficult to be there for her. Afterall, you don't really consider her your friend anymore. But she does need someone right now and you seem to be the person she wishes to turn to so.. just be a kind soul and try to help her. But if your heart isn't in it..
 
If your heart isn't in it.. then do the most that you can but not to the point that you'll pretend that you support her. Maybe advise her to go to her family for help or something.
 
Support her by locating the appropriate resources for her to rely on. It sounds like she has codependency issues, and that's something for a therapist to work on. Unless you're capable of helping her work through these issues, it's the responsible thing to recognize that your friendship or support is not enough to help her get better.