How do I get over what feels like hatred?

I just broke things off with a guy I had been with on/off. Only thing is I’m still going to see him around since we go to the same school and have the same social group. So I’m pretty much bound to see him. But ever since we broke it off seeing him, hearing of him, and even seeing his name makes me feel an intense amount of pain and anger and even disgust. Idk I usually don’t hate people and I don’t want to hate people for what they have done. But I almost feel like how I feel towards him could be hatred and It makes me sick that I would feel that way about a person because I’m not one to hate anyone. Please answer positively to this. I’m mad at myself for pulling myself this low to feel this way towards a person. I want to get to the stage where I am accepting and loving but I am far from that. How can I get to that level and how can I avoid feeling these things towards him.