I looked through his old messages like a dumbass

So my fiance has a tablet that he hasn't used in a long time and i was using it to watch netflix. I've never been the type to invade his privacy but I noticed he had messages on there from years before we even met and so I thought it wouldn't be a big deal if I peeked at them cause its not like it could be anything I'd have the right to get upset over. I realize now this is a stupid idea because no matter what if you read sext convos between your SO and other women youre gonna get hurt. I realized that a lot of his exes had MUCH better bodies than I do and especially now that I've had a baby (3 months ago) and I feel so awful about myself now. I breastfeed and my boobs are a wreck, i have stretch marks that look awful and a muffin top. I can't stop comparing myself to these other women and now I don't even want to be naked around him because I'm so ashamed. I know everyone has insecurities but mine are ruining my sex life and relationship and I don't how to get over it 💔