When I had enough of it, I let them know - sometimes verbally, sometimes not - that if they wanted me around, they should try acting like *persons* rather than stereotypical queens. If they persisted, I walked away. Sometimes, it worked. I let them know that I had boundaries, even though they didn't.
Your brother has no spine, and that's part of the problem.
Not being able to let go of being a victim is his biggest problem. He hasn't dealt with the pain. "Closure"is the biggest lie going. When parents aren't sorry and they're dead, there isn't going to be "closure". What there should be is a realization that it's over.