I am glad you are going to Al-Anon, using your phone list, and coming here.
You are right, knowing you are powerless and dealing with such a situation is very tough. I am sorry for what you are going through. All I can guarantee is that if you keep working your program and recovery, in time you will heal. You do not deserve the guilt that comes with dealing with such a self destructive person. In turn, I do not believe she deserves what she puts herself through.
I wish you healing, hope, and relief,
Lily