Why is my boyfriend such an a.s.s when hes with his friend?

today he called to tel me his friend john was coming over to his house, and i said ok cool come get me. he calls again asking for a soda. i say why? he dosent even like soda, then he gose off on me saying i was stupid dum ****** to ask such thing and that he hates that i ask him things. i said to him well im sorry to ask you such dum question but i know you dont like soda and you never ask me for things that i have at home. he was just fine befour he new his friend john was coming over. what should i do? its like hes a difrent person when he is with that lame a.s.s guy.