Need advice 😰😰

So I’ve been with my boyfriend for over a year and I’m still overthinking about his ex girlfriend and other things he’s had with girls!!! I really need some advice on how I need to get over it all. I know the girlfriend he had and the other things haven’t lasted as long as we have but it still makes me feel so insecure!! (He’s lost his virginity to the girl and has done like everything you could name - showered w her, threesome, done sexual things with other girls, and obviously done casual things like go out for lunch and whatever, and they’re all really pretty 😩😩).

I know that he loves me and cares for me and all that it’s just sometimes I get really upset about it and I don’t know what to do? I know I’m an insecure person which is why this is sorta hard!! I don’t want to go to him to talk about it because I have so many times and i get a similar answer every time I speak to him about it.

I need some guidance that would really help me not just being told to not worry about it and to focus on the positive blah blah, bc I do all of that and still feel like this.