I (don't) miss my ex

I broke up with my manipulative and emotionally abusive ex boyfriend 5 months ago. I felt no remorse, and I just felt free. I wasn't upset, because I knew how much better off I was without him. I didn't mean to, but 3 weeks later I ended up meeting a really sweet guy, and we have been dating for 4 months. I felt really guilty finding someone else so soon, but it honestly just happened, and he has been treating me amazingly and is the sweetest boy a person could ask for. More recently, I have found myself dwelling on my past relationship. I don't feel that I necessarily miss him, but I feel that I moved on too quickly to allow myself to heal. I find myself wanting to reach out to him for closure, to just tell him I'm sorry and I wish I took things slower. I don't know how to explain to my boyfriend, who has always been attached to my hip, that I want more space and I feel that I should take my time to heal. I don't want to break up with him either, because he is honestly the nicest person I have ever met and an amazing friend, and he would be absolutely devastated if we broke up. I also just feel toxic for dwelling on my past, and not being healed from my previous relationship. I should've taken my time to heal even if i didn't feel like i needed to. I didn't need to heal from being with him, but from what i went through in that relationship. We were super toxic, and he did a lot of yelling and blaming, and has done some things that really hurt me. I know I don't miss him, but all those events truly hurt me, and I wish I could just take some time to heal from that without worrying about hurting my current boyfriend.