you cant fix anyone, the best thing you can do is protect yourself physically, mentally and emotionally.i wold reccomend staying away, let her know how feel about her (and him) and create some distance, if she cant do school either transport or grades, she needs to change something.you have a life you need to deal with, and if you have to fix hers then yours will suffer. stay away let the chit happen and be there if she wants you after the chaos.if she cant see the guys dangerous, there is no point in you showing her by ending up hurt.she needs to put some distance between herself and the nutball, you need some distance between you and the chaos.doesnt mean you dont care, it means your smart enought to know when you cant fix things.