Bf lurking and liking my friends picture

Okay so my bf and I got into a really bad argument( he cursed at me so I left his house) and stop taking for a few days. During those few days we were not talking one night he ended up going though my friends IG and liking old photos of her (the most sexual pictures). he thought he would not get caught ( since he didn’t see that I followed her) and was caught off guard when I told him. He said it “seemed we were not together” bc of how bad our fight was. I don’t know what to do I feel embarrassed that he did that (since my friend sent me a screenshot)! And I’ve been feeling very insecure before this and even more now. Right now we’re taking a break but I don’t know if I should get back With him or not. He doesn’t see it as a big deal since it’s just a “like” but it really bothers me. He already came to apologize to me but it still bothers me.