I'm starting to think I'm acting like a crazy ex girlfriend
Really now? Why do you think you're acting like that?
I think about him probably too much.
Honestly, the relationship is over. You should consider moving on because nothing is going to change. Don't dwell on the past, it is not good for your mental health.
Yeah I might be crazy.
I don't think you beat yourself up that much! It's fine to still have feelings or think about the past, but sometimes enough is enough. If you have trouble getting over him, how about distracting yourself and enriching your relationships with your friends?