What can I do to get my boyfriend's friends to like me?

My boyfriend and I have been dating for almost 11 months but I haven't really been around his friends all that much because we don't live in the same town. Although recently, I was with my boyfriend and a few of his guys friends and I didn't know what to talk about because I don't know them well. So they started to make fun of me because they're under the impression I don't talk (I do, it just takes me awhile to warm up to people) and it really got to me because they were very immature about it. I mean, what am I supposed to say when they're making fun of me? It was to the point that when my boyfriend and I left, I cried because it hurt me that bad. What can I do for this to stop? Please help me.