Boyfriend watching old videos made with ex’s.

So I’ve recently caught my boyfriend watching his old videos he made with his ex’s.. but for a little back story, I met him through my sister. They were sleeping together at the time. And they took videos. I met him with I was 8 weeks pregnant, he became my bestfriend and came to every appointment with me as the dad is not involved. When she was 2 months old we started dating and for the last 15 months all my daughter has known is him. And things have been pretty good for the most part. But 3 weeks ago, while I was at work, I work graves. He was watching porn and masturbating. He started with one of ours, but then grabbed his old phone and watched the ones made with my sister. I told him that it is beyond disrespectful to me and my daughter. And since then I’ve been debating everything. I’ve been distant, hardly touch him. I can’t stop thinking about it. What would you do in my situation?.