i was an army brat so i travelled all over, made friends everywhere. i think your girlfriend's friends r immature, threatened by u, jealous and r trying to undermind u. sort of a herd mentality going on. when some people get out of their comfort zones they will act out. if all that these friends can do is give u back handed compliments and sarcasm then its about them and not u. its a way to level a situation and weaken someone's self esteem. instead of rising to your level they will pull u down to theirs. latent hostility thing. they r being vague with u on purpose to control u. they cant directly come out and say or do something. i wouldnt put up with this behavior or waste any time on them. they sense u r on to them. dont personalize this or try to explain yourself to them, it just hands control over to them. your instincts r good. just unload them and be glad they r gone.