Wanting a different feeling but struggling

Hello! I had an experience 4 months ago. A very good guy friend told me that he’s loved me for years and wanted to be with me. I have loved him too and it felt like being in When Harry Met Sally and I felt so happy. I then learned that he was sleeping with at least two other women at that time and he also changed his mind and seemed to have no empathy for the impact this whole thing had on me. I see so many thoughts in there that I’m making true and are causing me pain. The action I took was to block him on all media and stop going to any place I’d see him. I did not tell him I knew about the other women. I am finding myself still having obsessive thoughts and sadness and wanting him to never be happy. I want a feeling of loving detachment and to feel supportive of his future happiness but I am putting things in the C line that aren’t Cs. Help please!