How do I move on?

So a while back I was with my ex. Nearing the end of our relationship I realized how badly he damaged my mind and that’s when I cut him off. About a week later I started dating my good friend. He treats me like a queen and is so much more gentle and loving with me. I love him so much and don’t want to lose him. But whenever I try to do sexual things with him I get terrifying flashbacks of my ex. My ex unfortunately managed to pressure me into doing a lot of sexual things with him before I was ready. He pressured me into giving him a bj outside the movie theater because “he had paid for everything that day” and “he deserved one”. I felt gross and hated myself after if. He also pressured me into trying to do anal (with fingers. Thankfully I didnt let him get past that) and he pressured me into letting him put his you know what against my you know what. That was the last straw and I was almost at the point of wanting to kill myself. I feel better now that I’m with my ex and I feel safe with him. He always reassures me that if I’m not ready he isn’t. And he will always wait for me until I’m ready. I just want to forget everything about my ex. I want to erase him from my mind. I want to bad memories to go away.