I am not physically attracted to my boyfriend

Me and my boyfriend have been in a relationship for about a year now. We're in an LDR as we go to different colleges. He's honestly the sweetest person I know and is super thoughtful but I've never found him attractive or good-looking. We text frequently but I'm worried if I'm just overthinking or not. We also did break up and get back together several times so I'm not really sure what to do. I know he really loves me and I don't want to hurt him at all. He also has doubts that I don't find him attractive as he knows I'm more sexually attracted to women.