I don't like my boyfriend's dad and I actually kind of resent him. What should I do?
Why do you resent him?
He made me feel like shit most of the time, and generally he is an asshole to everybody.
It's usually wrong to resent people, especially your boyfriend's family, so you should try to find some common ground.  However, if this man is being disrespectful to you most of the time, it might be best just to avoid contact.  Your boyfriend will probably understand, since this seems to be common.
I will manage to stop resenting him and even sit closer to him.
I hope you work out a plan that works for you and your boyfriend. It's going to be tough but you should try to get along with him.