Generally, I deal with this by just avoid all animal/food topics, and tuning out when they go off about the 'yumminess' of meat (which they seem to do just to try to get a rise out of me).....
i always found that amusing, when meat eatering friends tell you all about their last meal. for example "hey guess what... i just had a steak
." why do you feel the need to tell me what you just ate? you don't see me walking around telling people "hey, i just had some vegan hot dogs."
i'm not your mother, you don't need to report your meals to me. they are trying to get a rise out of you, so don't give them the satisfaction. let it roll off your back. when they tell you they are eating a steak, just look unaffected and say "and.... ? what's that got to do with out current conversation
?" or "thanks for sharing tha piece of info... but back on topic...
of my close friends are vegan. the few vegans i do know, i don't get to hang out with very often due to work schedules or relationships. so i am in a similiar boat as you.
i would listen to michael's advice, and tell them how it makes you feel. and i agree with him that the ones who make the most fun are the ones who know that what you are doing is right. they are generally just feeling guilty that they can not make the same commitment you have, even though they know in their hearts that they should. they can't come up with a good defense, so they just ridicule you instead. every single one of my friends, even (or maybe especially) the most die hard meat eaters, has come to me in private and told me they wish they could do what i am doing. they just feel like they lack the willpower.
of course when they are in public, they go back to cracking vegan jokes.