Either me or him... PICK!?

My bff is dating this guy 4 the 3rd time.The 1st time he sed his parents wouldnt let him go out so he couldn't see her so he broke up with her but she thought that it was also for another reason then the 2nd time he broke up with her saying he no longer had an attraction to her and didn't want to date her any more.Then just the other day he asked her bac out and even though my bff told me she didn't want to go back out with him she's now dating him again.Everytime this @$$ hole broke up with her I was my bff's shoulder to cry on and she was always sayin how much he hurt her and how she could nvr date any1 again and all she could talk about was her x.So now that she's goin back out with him I have stopped talkin to her cuz she won't listen to me about how much of an @$$ her bf is and that I think he's cheating.I think that if she is going to go out with this loser than I'm no longer going to be her friend and mayb she'll finally understand that she needs to dump him.Is this right of me?