What should I do about hating my brother-in-law and his wife?
Why do you hate your brother-in-law and his wife?
My brother-in-law is a jerk. He's so mean and his wife is so ugly. She swears at me.
You really should not let your personal feelings get in the way of respecting your family. They are family and you need to get along.
So I'm supposed to be nice to him and his wife just because they are family? I'm not going to do it.
Try talking to your family about how you feel. If they are not understanding then it's okay to distance yourself from them. You don't have to involve yourself with toxic people just because they are family.