For what it's worth, Aurora, every now and again at work, I bump into the girl I thought I was going to marry. In fact, I bumped into her two weeks ago. And every time I do, I blow her off.
Why?
Long story short, I'm fortunate I didn't marry her. When serious situations arise that test and reveal someone's true character, you have to pay attention to what you see. In my case, a serious situation came up, and she revealed her true character. To be blunt, it's rotten, and there is no indication that she'll ever have anything but a rotten character. So I ice her, and at times, I've been quite rude. I don't care if I'm rude. The only thing that matters is protecting myself from someone I know to be bad news. And for that, I will never apologize.
The only way I will have anything to do with her is if she shows genuine contrition for being such a selfish, self-seeking eff'ing beeyotch. But on a probability scale of 0 to 1, with 0 being no probability and 1 being the event will happen, there's about a 10^-6 chance she'll do that.
In your case, your AXBF is bad news. There is no indication he will ever be anything but bad news. And there's one of two ways you can handle it. You can hold out a slither of hope that one day, seeing him will be like seeing any old friend. Or finally give yourself permission to take care of yourself, ice the *****, and cut off ties with his family for good.
Keeping those ties will not allow you to move forward. Neither will holding out hope that he'll smarten up. The chances he'll smarten up are the same as my ex showing contrition, and maybe less.