He pulls away when we ask him too many questions, but I'm curious and kind of concerned about what might be going on. At this stage of adolescence there can be many reasons for leaving old friends behind - some of them cause for concern and many of them not. Kids are changing rapidly at this age, going in new directions and often finding new friends who share their new interests.
Teens also can be fickle and sometimes shut people out in hurtful ways.
It's possible that your son may be protecting himself by pulling away from friends that are engaged in behavior he doesn't like. A loss of interest in activities that normally give him pleasure Signs of alcohol or drug use As for how to learn more about what is going on with your son, the best strategy with adolescents is to be there to listen, but not to push too hard. I remember with my own son that many of our most intimate conversations were in the car. It may also help to just let your son know that you've noticed that he doesn't hang out with his old friends anymore and that you've wondered how that feels to him. Without pushing, let him know that you're willing to listen if and when he wants to talk.