Well, without knowing his actual situation, I would hazard to guess that he might not be getting the affirmation that he needs among his peers at school and at other activities. You are already helping him in trying to find peers who are kindred spirits. Unfortunately, at a young age, children are already internalizing others' perceptions. On the other hand, perhaps he is just hypercritical of himself and the best thing you can do is not to over-react but casually point out a few of the genuinely cool things about him.
