retroactive jealousy (mentions sexual activities)

I've been with my boyfriend for almost 7 months and i still can't get over the fact that he's had multiple sexual partners in the past - more than I have. He's been part of hook up culture whereas I was in long-term relationships and personally i don't think i could ever have one nights stands because of the emotional connection attached to sex. So i can't help but think that he doesn't see sex on a spiritual level as i do and that he doesn't feel any different when it comes to me, as his first serious and long-term girlfriend. I mentioned this to him a lot of times and he promises that he feels so connected and so attracted to me and that i'm all he wants and that. Despite all of this, i still think that maybe he misses going to random parties and messing about, or that he thinks of other people when he's with me. There's been times when i felt uncomfortable when him and i were being intimate because i couldn't stop thinking about his past experiences, or that he thought someone else was prettier than me or had a better body. It got to a point where i had anxiety attacks when he mentioned us going to his home country just because i know he's had a few hook ups or friends with benefits there. He always talks to me about his country and his desire for me to meet his grandparents and go dance with me and take me to the beach, all in all very relationshipy things which are very very sweet - but all i can think about is what if he takes me somewhere where he's been with other girls in the past? or what if we see those people and they're going to look at me like 'oh i did things with your boyfriend'? We're both very jealous and, when we first got together, he told me he was experiencing retroactive jealousy too because he couldn't bear to think about me being intimate with other people. Recently, his jealousy has gotten a lot better and i asked him how and he simply said that he came to terms with the fact that he can't change my past and he truly sees himself being with me long long term.

But why doesn't it work for me? I'm asking myself if i would want to be with anyone apart from him and the answer is obviously no, so i should believe him too. But i've been through major and ugly heartbreaks when people have told me things like 'you're the prettiest girl i've ever seen' then cheated with someone that was the complete opposite of me so it's simply hard for me to trust my current boyfriend 100% when he says he only wants to be with me. He's truly so special for me and i don't want to ruin our future plans just because i can't get over something that he did before we even spoke to each other.