I have a (half) ''brother'' who cut me out completely. I think he has severe NPD. He didn't even know me. I guess I do see him as ''all black'' now or close to that. I was only ever kind to him. Grrrrrrrrrrrr

I wouldn't put up with your sister as things are. But I'm not sure that I would cut her out completely. If she is not willing to change though.. maybe I would.