Should I cut ties with my homophobic family?

My boyfriend and I visit my family every year for Christmas, and every year they treat him rudely and unfairly. This is solely because they do not accept my sexuality, and they blame him for it. I have made it very clear that if their behavior continues, I will no longer visit them on holidays. They always agree to my terms, but as soon as we arrive, they immediately go back on their word. To make matters worse, I visited them alone this summer for my birthday. During my visit, the daughter of a "family friend" "just happened to stop by." It was very clear to me that this was a set up. When we received a moment alone, I told her that I was in a happy, committed relationship with a man. Her reaction showed that she was entirely deceived. I left the house, and I have not spoken to my family since. I have no desire to have a relationship with them. Should I permanently end the relationship?