Ended the relationship with my boyfriend because he was liking pictures.

I'm a 25-year-old woman and my long-distance boyfriend is 29. We’ve been together for nine months, and our relationship felt like a fairytale. We had known each other for years before finally getting together. He would fly out from another state every few months to spend time with me, treating me exceptionally well throughout our relationship. I genuinely fell in love with him and appreciated how he treated me. However, there was one issue: he frequently liked photos of other women on Facebook, particularly one in particular. This really bothered me and felt disrespectful, so I brought it up with him twice. Each time I expressed my concerns, he would shut down and go silent, unsure of how to respond. I found this very frustrating, but I did my best to remain patient and give him time to process. His responses usually included comments like, “You think every guy doesn’t do this?” and “We’re not married, so I don’t think it’s fair for you to ask me to stop doing that.” It seems that I can’t request respect until we’re married, which leaves me feeling disillusioned and confused. Despite everything, he has been a great boyfriend in many ways. He made me feel safe, cherished, and invested a lot in our relationship. If he was willing to put in the effort to visit me regularly, why couldn't he just agree to this simple boundary? I'm torn about whether I should reach out again or stick with my decision to give him space. I genuinely cared about our relationship, and the thought that he must have loved and cared for me makes this even harder to understand. I want to clarify that I'm not looking for validation regarding my feelings or anyone to tell me I'm insecure. This is simply a boundary I've established. I can’t be in a relationship where another woman is constantly aware that she has his attention. I don’t understand why he could be so wonderful in other aspects yet overlook this important concern. I’m tempted to reach out to him, but I also want to maintain my self-respect and let him take the initiative. Am I making a mistake by holding back, or should I send him a message? I'm really unsure.