It hurts to say but honestly I don't really feel that close to my best friend anymore.
I'm sorry to hear that, why do you feel you're not close to your best friend anymore?
He's crazy, and we aren't compatible.
It's okay to grow apart from someone if you don't feel that you are compatible any longer.  But you should always be honest with people if you don't feel close to them anymore, don't just abandon him without letting him know how you feel.
I'm going to use the reason that he is crazy to hurt him and show him who is boss.
You shouldn't do that, hurting his feelings isn't going to help the situation at all. I think you should simply tell him that you feel your growing apart and you both should take time away from each other.