jealousy and trust

so I have self confidence issues. My ex cheated on me almos the entire 7 months we were together. I'm one of those girls who says if youre with my you're with me. No porn. Nothing like that. just about a month ago I found porn on my current boyfriends phone on reddit. he claims it was just because he use to watch it and it just recommends things to follow, but I also found it in his saves. he's never given me reasons to think hes cheating but he also doesn't communicate with me very well. just this week I found out he use to screenshot his friends girlfriends nudes and Photoshop and do weird stuff to them. its his past I can't really be mad about it but it makes me nervous he's shared my pictures. I also don't like it when he watches shows that have a lot of nudity (Game of thrones, sons of anarchy) but I don't stop him bc I don't want to be controlling. I just need advice on how I can cope with this.