I've liked a straight guy on and off

Hi! I'm a 16 year old gay guy and I've been facing the problem of liking a straight guy. This has been going on for about three or more years (it's been on and off) and I'm not really sure what to do anymore. He is my best guy friend and he feels the same way. We are really close and we tell each other everything that's on our minds. He does know that I've liked him on and off, and I do tell him when I do like him. He understands and tries to reassure me that we are just friends.I understand that we won't ever be together, and just really good friends, but I always have false hope and can't really get rid of it. I get really sad and jealous of whoever is dating him and it's kinda destroying me. I have thought about talking to him about taking a break from being friends for a little or something.... I'm not sure anymore. I want to keep our friendship, but I feel like I might be in love with him? I'm not sure of my feelings and I want things to get better.Thank you for reading