I think I’m in love with my best friend

I’m terrified rn. We are both 16, almost 17 years old and we have known each other for our entire lives. Hes always been like family to me, but recently Ive begun getting weird feelings that I might like him romantically. It scares me because we have so much history? and I don’t know what I would do if I lost him. Hes literally everything to me. But at the same time I feel like we have too much from the past, and it would be weird. Idk I just feel jealous whenever I think of him having a gf, and I feel guilty about wanting a partner

Sorry for the weird rant I just don’t know anymore