I think I'm on the asexual spectrum?

So this is kind of awkward for me to write because I'm just trying to figure out my sexuality now at 24 years old. I've always known I never experienced sexuality the same as everyone else, I've always been super uncomfortable talking about sex, even still now with my partner of over 5 years. I've been struggling with my sexual identity because I thought I was just a typical heterosexual with a low sex drive as I still engage in and enjoy sex sometimes. The thing is, I really only feel super passionate sex when I'm in the beginning of a relationship and otherwise have no idea what "turns me on". My partner and I still have sex occasionally but it's almost always because I want to please them and not because I want to (side note: my partner is very understanding and has never forced sex on me, it has always been consensual). Sometimes I almost feel like I'm asexual because I don't view sex as necessary in a relationship but something nice to enjoy once in awhile. It's difficult when my partner sees it as a deep loving connection and can't understand why I almost never want to especially when I always wanted to at the beginning of the relationship. I had read something recently about greysexuality, which is what led me to further questioning as I had no idea it existed. I don't know, I don't entirely hate sex but I don't feel like I experience it the same way everyone else does. I don't know if anyone has had a similar experience or any advice that could help me figure out what's going on with me.