My boyfriend's father hates me, what can I do?

My boyfriend an I am both 20 years old. Currently we are both living with are parents, just because of various financial reasons. We have been dating for about three years now. We are both very serious about the relationship and want to spend the rest of our lives together. My currently problem is his father's and sister's deep hate for me. I don't know when it started, maybe when they saw we were serious, I think it is because they want to have control over him. The hate has grown to where they hate my whole family and say mean and untrue things about all of us. I have never been told these things to may face, but my boyfriend tells me most of them and I over hear others.

I have tried for 2 1/2 years to get them to like me and see that I am not an awful person, currently I am just tired of trying. I feel that this is a battle I will not win, so I have stopped trying at all. I avoid them whenever possible, and speak as little as possible to them.

My boyfriend doesn't want to cut contact from them when we marry, and I don't want him to have to, but having to see them any more then I have to just sucks. It has gotten so bad that I hate to be in the same 100 feet with them. I am not sure how to find a balance with everything...