[23F] and [25M] are engaged, and nothing is changing.

I apologize for the lengthy message, but I really need to share what's been on my mind. I'm 23 and my fiancé is 25. We've been together for over five years and are planning to get married this year. Before him, I was in a really bad relationship, and he helped me understand what true love is. However, sometimes I feel like he's taking me for granted. There have been moments when I should have walked away, but I chose to stay. During a deep conversation we had, I expressed that I don't think he believes I'll actually leave him if necessary. We've experienced our fair share of ups and downs, but we’ve managed to overcome challenges together. About a month ago, we had another serious talk where I shared that I'm feeling disconnected and not quite okay. We even considered taking a break but ultimately decided to work things out. Recently, though, we’ve been struggling with intimacy. I mentioned how this affects my self-esteem, and he reassured me that it’s not about me; it’s him. On top of that, I expressed my discomfort with him searching for a girl’s OnlyFans name on Instagram and then looking her up on Reddit. While I don’t mind if he watches porn, this specific behavior has been bothering me. He promised to stop. However, we tried to be intimate last night, and it didn’t go well. When I asked if he experiences the same issue when he masturbates, he accused me of thinking he does it more than he actually does, which wasn’t the case—I was just asking. He eventually admitted that he still has the same problem. Today, I noticed he visited a girl's OnlyFans account, one he had already been looking up on Reddit. It's frustrating because I don't understand why he needed to look her up again. I know he doesn’t pay for OnlyFans, but I feel like I’m stuck in the same conversation repeatedly. Should I keep waiting for things to improve?