welp I guess I'm jealous

So a few months ago I was looking st Instagram on my boyfriends phone and saw his most viewed people were 2 girls we went to highschool with. It GREATLY bothered me at the time especially bc he never looks at my social media at all. He has since he has deleted all of his social media. These girls were never people that he was close with or anything but we knew them briefly. One of the girls posts really revealing photos of her body so it kind of made sense but the other didn't really. It bothered me more that he looked st the girl who didn't post revealing photos for some reason because I thought he may have some further interest in her besides her looks or something? Idk if that makes any sense. 
Anyways I don't know what to do because this still is bothering me but we already have talked about it in length and I know it's bad to open old wounds. He has said that it doesn't change anything about his attraction to me. We do have sex all the time and he tells me I'm beautiful. I guess it's stupid but I feel myself craving more praise and reassurance and I don't know if I'm wrong to be feeling this way or whatto do. Advice?