I'd like to give your friends the benefit of the doubt, and not believe that as your real and true friends they were very pointedly being cruel. Do you guys banter, or talk shit, in good fun? Me and my siblings are like that. I know this is common, especially amongst groups of guys. This by no means excuses the behavior, but were they fully aware this was hurtful to you? Would having a heart to heart dialouge help? I sincerely hope a discussion can be had, and that their crappy "joke" wasn't intended to actually hurt you. You deserve better, OP.