It doesn't at all make you a bad friend to set boundaries. If you don't protect yourself, then who will? If the person is sincerely sorry and makes visible efforts to change, that's one thing. But when someone gives half-hearted non-apologies, tries to put the blame on everyone but themselves, and makes no effort at reform, then you have to take a step back. When you love someone, it's far easier to see the pain they feel than the pain they cause, but some distance might help. Please don't beat yourself up for treating yourself as a human being deserving of respect!

Hugs to you, thirty Shades.