He apologized, but said he doesn’t remember it

I (18F) had a conversation over the phone today with my ex boyfriend (18M) who I’m pretty sure sexually assaulted me on multiple occasions. I explained to him the details of what I remember happening (ex. he would ask me over and over again after I said no, he shoved his dick down my throat without asking me, one time he was putting random objects around my room inside me while I was asking him to stop and he just kept doing it, our first time I cried and asked him to stop and he just kept trying to force himself inside me, I woke up to him grinding on me and told him to stop and that I wanted to be left alone to sleep and we ended up having sex even after I told him no). He apologized but says he doesn’t remember any of these times, and he doesn’t even remember waking up at all that one night. He also asked me why I didn’t fight him/push back, why I didn’t seem as bothered by it as I should have, and why I didn’t break up with him. I told him I tried multiple times to bring it up with him but he always dismissed my request to talk about it, and that I really didn’t process what had happened until over a year later. He said he really is sorry and that he feels icky about it. I want to believe that it was an accident and he really doesn’t remember, he has been raped in the past so is it possible he had a memory lapse?