Any advice?

my boyfriend & our relationship started off a lil rocky. When we were in our teens, he left me & didn’t want to be with me. After he left me, time went by and I started talking to a friend than it became a relationship but noticed it was a toxic relationship. He would demand photos and tell me if I didn’t send them, he would expose me & put my pictures online, that he would find my parents (he found my dad once btw) & tell me he would expose me etc. & I was young & very vulnerable because I was going through a lot. He would call me

Names, tell me he would hurt me etc. so I was very scared of him. I stopped talking to him but it was hard I felt like if I left off on bad terms, he would hurt me any way he could. My ex (boyfriend currently) came back and told me he regretted everything and I was single and I said yes because I did love him still. We were a long distance relationship but he’s only lives 30 minutes away. While we were first together my toxic ex would text me and I would text back because of out of fear. There would be no emotion or love in our messages because I didn’t feel like that towards him anymore and I had to respect my relationship. My boyfriend brought this up after 4 years into our relationship & he told me that I cheated on him. Which I did not and I explained to me how I was scared when my ex would text me and he knew that. He even said something that I never recall ever saying, “that I didn’t know whether to choose between him or my toxic ex” which I know in my heart that I never said that. Mind you, when my boyfriend brought this up , he was a bit buzzed from drinking. I understand I should of never replied to my ex and apologized to my boyfriend and explained the situation to him. The last time I talked to my ex. I lied to him and told him I was married and was pregnant, just so he can leave me alone forever. He believed me and I had him blocked on insta so he couldn’t see if it was real or not. It just makes me feel horrible that my boyfriend thinks I cheated on him when I would never do anything to disrespect him in that way. He said he forgives me but I just feel horrible that he thinks I cheated on him. Whenever my ex would text me, I would always tell my boyfriend that he texted me & that I was scared he would do something. I never hid it from my boyfriend because I wanted to be honest with him. I know me texting an ex was not right and I apologized to my boyfriend and it something I’m not proud of. I just feel horrible because He called me a cheater when I’m not.