Is normal that a guy changes a lot after rejection?

I rejected a guy I wa seeing for some time. We kissed and went out. He was always really funny, smiled a lot. We didn't talk for few months. Recently we started talking again and we are friends. But often he just comes says hi and doesn't even smile. doesn't pay any attention to me nor my friends an dhe used to talk to all of us a lot. He is much more quiet.

Is normal that a guy changes a lot after rejection?
Post Opinion