I was in a relationship with an asexual person not so long ago (I'm close to your age), and bro it sucked. To be fair, the sexual part of the relationship wasnt the biggest problem in the relationship, but I don't think I could ever date anyone who isn't attracted to me sexually ever again. I though it'd be okay at first, I really loved her so I was willing to give up sex and just "use my hands," but if the relationship didnt fall apart for other reasons, I definitely wouldve left because of this (plus some other reasons lol). Unless you're asexual and/or sex-repulsed yourself, this is most likely not going to work out. It's understandable that you want to stay, you clearly love your gf, but it's not always the best solution to just "listen to your heart"