Am I being unrealistic for believing I can mend my relationship with my avoidant boyfriend after a major disagreement?

My boyfriend and I have been together for about five months, which, while not very long, is my longest relationship, and I feel a deep connection with him. We do have the occasional argument, but nothing that concerns me too much. We spend plenty of time together, share a lot of intimacy, and have built a close bond through various experiences. I’ve developed a strong attachment to him. Both of us have had avoidant tendencies in the past, but his behavior has made me more anxious, which has been challenging for me, and it's something I'm actively working on. A couple of nights ago, after returning home from shopping, I was really tired and laid down on the floor. He came over to give me a back rub, and I asked him to pop my back, which he usually does. In a playful mood, he began pressing on my back and bouncing a bit, but I suddenly found it hard to breathe and asked him to stop, which he eventually did. Once he stopped, I found myself crying and hyperventilating. He immediately apologized and wanted to know if I was okay and if he had hurt me. The truth is, he hadn’t hurt me at all, and I wasn’t angry with him. While the situation was frightening because I couldn’t breathe, it triggered memories of past experiences where I felt powerless and afraid for my safety. I knew he meant no harm; he was just being playful, but it stirred up emotions tied to past traumas that I thought I had processed. After I calmed down, he asked me more about why I was upset. I explained that my tears weren’t about him but were related to past traumas, and I recounted two specific events: one involving my mother and another where I was taken advantage of by someone, both from years ago. It took me nearly twenty minutes to share this while still crying, and when I finished, he went quiet. He received a phone call from his dad and returned ten minutes later, saying he didn’t want to be physically intimate with me anymore. I was shocked and confused. He expressed that he couldn’t touch me without thinking about my traumatic experiences, which I had only briefly outlined. He mentioned he didn’t want to handle my trauma. I was devastated, trying to make him understand that my trauma is my own and hasn’t interfered with our intimacy. It was frustrating to see him make it about himself when it had nothing to do with him. He said he wanted to take a break, and while we could spend time together later, he wouldn’t want to engage sexually. I just couldn’t accept that and ended up having a huge emotional breakdown beside him in bed, struggling to comprehend what had just occurred. I never expected such a reaction, especially since we had been doing really well and had a vacation planned for the coming weekend. Now, I’m feeling lost and heartbroken. I desperately want to find a way to communicate with him and help him realize how hurtful his response was to my vulnerability. I’m willing to do whatever it takes to restore our relationship to what it was before that night. I wish I could turn back time because he is truly the only person I have, and losing him feels unimaginable. Is there a way to reach out to him without pushing him away, considering he tends to avoid confrontation? How can we get back to the place we were before this incident?