My future sister-in-law is a horrible person. She makes everything about her and if she feels like it's not, she makes everything hell. It's like walking on eggshells. She also has some sort of spell over my FH and his brother. When she's around, they bend over backwards for her and do what she wants even if it goes against what they would normally do. And at the time, they act like it's no big deal. She's made it clear that she will do what she can to make sure my FH and I don't have a relationship. I tried to give her a chance but she threw me under the bus by telling me one thing and then lying to my FH making him think I was trying to ruin things. On top of all that, she has been an awful person to my FH.
At first he had cut her off. He was done. But then she used her spell and dragged him back in to where he just pretends and forgets all the horrible things she has done. Now he wants to invite her to the wedding. I have made it clear I do not want her there. She will do what she can to ruin the wedding and make me have a miserable day. She'll convince him to do something or allow her to be apart of the wedding. Whenever she's around, he folds to her will. We've talked about thia before and he agreed not to invite her, but he just brought it up again. He feels that if he doesn't invite her that he will lose a relationship with her forever and that she deserves a second chance. I've told him that our wedding isn't the place for that. Plus he has given her chances after chances.
I basically feel like it's either I have a miserable wedding with potentially a blow up or he has a miserable wedding because he feels he lost a relationship with his sister. I don't know what to do and at this point, I feel like this could ruin our relationship.