Thanksgiving dinner help!

A
Might be a little long o an explaination but I really need advice. This year my boyfriend asked me to come to thanksgiving with his family. Every year prior to this I have went to my best friends. I don't have much family and those that I have don't celebrate. I was hesitant to tell him yes I would come because his parents don't seem to like me. Actually I know they don't. They believe that I am the reason bad thing happen in his life and because I come from a poor dysfunctional family and he is from a well off "functional" that there is no way I could be good for him. Last week, his parents and him got into an argument and they said "Don't bother bring April around this house anymore!" And also they said if I actually wanted to have a thanksgiving this year I would have to ask his grandmother because the parents don't want me. My BF is still trying to get me to come to his family's dinner but I told him I made other plans with my best friend and if he wants me to come I won't until I get a personal apology from his parents (which he said would be very unlikely). Was I wrong to make other plans? Should I just put up with his family now in hopes that one day they will respect me? They have known me for almost a year already.