He can carry on with everyone else but just not me. It's crazy.
It may be because he likes you so much he is afraid of doing something wrong to annoy you or make you not like him as much. You should let him know that he can be comfortable around you. compliment him a lot and let him know that his opinion matters to you. Try not to criticize the way he acts or things he does. It'll help a lot and he will feel like he can be more like himself around you.
i know i have trouble talking to the guys i like .....so i think he i just afraid he will say something stupid in front of you....just let him know he is the only one you wanna be with
He's probably just really nervous, how long have you been together? if it's just the begining of a relationship (a few months) just just give him awhile to warm up :)
I vote plain old nerves.