Raising a boy

I thought I would have to take special care with Glee because she is a girl. I spent a lot of time helping her to build her confidence, her self worth (we are still working on that one) and her empathy. I thought Thomas would roll with the punches. I was wrong. It seems he needs more help with his confidence. He spends a lot of time trying to get people to talk to him. He yells "HI!" to his friends, a lot, almost to the point of being annoying. Last night he had a nightmare and this is what he told me... "I pretended I didn't have anything to play with and no one was my friend!" My pretended he meant that was what happened in his dream. He has a very hard time when people ignore him and there are a couple of kids who know that and do it to him on purpose. One boy does it and I just want to smack him. He does it to his sister to, and it makes her cry and he doesn't care. I need to steer Thomas away from that kid, but now I find that a boy I thought was one of his good friends is doing the ignoring thing to him too! So, dear friends, any thoughts on this? How can we raise a boy's confidence? I may need to go check out some books from the library. He is such a sweet and smart boy, and he is generally kind to others, although he is picking up some habits I don't like. I thought I did a good job preparing him, but I can see kindergarten is going to be more brutal for a boy than for a girl.