Toxic friends are bad, obviously. There's nothing you can really do about it other than what you are already doing. I"m going to get "religious" on you. \:\) Pray that she makes new, better relationships with other people. God doesn't want people to be unequally yoked with unbelieving friends. It doesn't mean that she should never hang out with her, but the relationships that influence you the most should be with people who strive to live God's way.

From personal experience, I'm learning to distance myself from my egf. When I'm with her, I feel bad for some reason. She seems to suck everything out of me. I can't just stop being her friend, however. I feel like she needs me at times, and it would feel wrong to ditch her altogether.