I (22F) have been with my bf (23M) for 3 years and just found out that he jacks off to instagram photos of other girls. The other day I was looking through his hidden folder in photos where he keeps our 'intimate material' that consists of things that I've sent him of myself and things he's filmed of us – because I wanted to surprise him with something different that I had not sent him before. I came to find in that a screenshot of an instagram photo of a girl that we both know, with porn in the corner (when you pull down a video and it stays as a small screen while you keep using your phone) as well of another screenshot of an instagram photo of another girl we both know in the folder as well. These weren't even photos that I would consider sensual or revealing, just a normal instagram post of them from a formal event.
I confronted him about it and he got a bit awkward as expected and was avoiding giving me an answer and said he didn't know but then – pretty outright – he said he was probably jacking off to her. I was speechless. After getting pretty upset, I dug deeper because I just couldn't understand why he would do something like that. He just apologised and said that he didn't know. I asked him if he knew it was wrong and he said yes. And then asked him if it's something he does regularly, he said kind of and that it was something that him and all his mates used to do back in school too (He's been out of school 5 years now). But the main thing that's bothering me is that I asked him if I hadn't found it and brought it up would he have kept doing it, and he couldn't really answer but mumbled probably.
I have no issues with him watching porn and understand men finding other women attractive is normal. But this felt like a whole new level. And also now it bothers me because previously I also know that he saves photos of pretty girls (both celebs and some of girls he know/he and I both know, which was something I kind of overlooked before but now everything is piecing and I wonder if it had all just been for his 'spank bank'.
I love him very much and we've had a really wonderful relationship other than this and our intimacy is great too, so I'm very conflicted about how I feel or should feel. I've been crying for the last 3 days thinking about it and feel just disgusting, even more insecure and disrespected. I know it didn't cheat on me, but they way I feel now, almost feels as though he did. I don't think I want to leave him over this but I need some advice on how to navigate through this, and how he can help me navigate through this or what he can do to make me feel secure again.
TL;DR – Bf saves or screenshots normal instagram photos of girls we know and masturbates to them while watching porn and now I feel horrible. How do I past this? And what can he do?