No sex drive 😔

My boyfriend and I have been dating for about year now and I know that he's my person. The only problem is my lack of a sex drive. I'm on antidepressants and have been for 3 years now, and I've noticed a decline in my sex drive since then but now, being in a comfortable, amazing relationship with the guy I'm almost certain I'm going to marry, it's almost faded completely. We still have sex but sometimes we can go without sex for about 2 weeks, which, at 22, Id say, is not all that natural or even healthy particularly because I had such a high sex drive when I was younger (prior to when I was 19). He says he understands and that our relationship isn't all about that stuff, but I still feel awful when he's keen and I'm not at all. In addition, despite how much he wants to be, he's not the super fit carved out abs type of guy, so he often questions if I'm unattracted to him, which is not the case at all. It's just I often have to force myself to do it, even though it's fun and I o.g. nearly every time, I'm just not all that into sex anymore. Is there something else that's wrong with me? Or is there any advice someone has for me? It's getting to the point that I'm seriously beating myself up out it and I'm worried that it will put strain on our relationship in the future. Xx