I tend to stay away from large groups personally unless it is a concert I am dying to see. I am not totally anti-social, but I have a thing where I do get very nervous and scared when I am around people I do not know and even people that I do know. I'm a loner. When I was younger I went through a lot of emotional pain and scaring that I guess still has not fully healed. Thats why I do not go to parties or bars and generally spend most of my time studying and smoking. It's just how I am. I am fine when I am alone watching TV or reading.

You seem like the outgoing type. Are you sure that you are just not jealous that he is hanging around a lot of his friends? Maybe he did not feel comfortable around your friends so he wants to be around his.