Confusing situation, opinions?

Well lately, this "friend" and I haven't talked to each other. Last year we used to be best buds and all, but ever since the new school year, all he's been tryin to do is act cool and stuff, and in order to that he had to hang out with me less (which in this case means he'll ignore me), so that I don't ruin his image for some reason. I don't get why, but the people he's trying to fit in with, I'm already good friends with most if not all of them. I wasn't too pestered when he announced his birthday party, and I wasn't invited, but recently I heard that in favor of picking me and one my close friends, he chooses two girl, who almost never talk to him. My first reaction was "Wow, wtf" but I'm a person who thinks too much xD. I don't talk to him much anymore, because whenever I honestly try to be friends with him, he acts all annoyed with me even though he's not talking to anybody, and all I ever got to say was a "Hi", or "Sup". Can anyone give me an opinion or something, just so I can move on from this? (btw I'm a bit annoyed that he chose 2 girls who never talk to him over me who's tried to be his friend.)