Im hopelessly in love what do i do! but its long though?

Me and him have been friends since 7th grade, at first its like any boy girl relationship, compeletly harmless and innocent, then 8th grade, people started to think we go out, we played it off nothing of it, now were freshmen, 99 percent of our circle of friends think we should or are going out, even people we hardley know think we do, we almost crapped a golden brick when we got seperated during football games in the stands (were both in band) almost ka joined at the hip. But he likes someone else, and im fine with that, i WANT them to get together, to see him happy, but i find myself getting jealous easily, for no reason too. He hangs with other people, sure go have fun, but later in the back of my mind im like wtf. He buys a necklace for the girl he likes im like awww its so cute, then later on i get kinda miffed about it, he asks her to the military ball thingy im like awwwww! so cute, in his lil rotc uniform in all, then later i get kinda irritated. i play it off, but every little thing he does is amazing like ill burst into tears if he does something manly, like this one time this fat kid was messing with me and he went HAM he went beast on him about to kick his butt, like if anything happend to him idk what id do, like last week i had a terrible day, and he let me cry on his shoulder during lunch infront of everyone and didnt care. WHAT GUY DO YOU KNOW WOULD DO THAT?! hes like everything i wanted, words cant describe it. I told him i liked him last semester and were over it, but now its even worse, i think im falling head over heels for him, everyone sees it. We can talk for hours about dryer lint i swear,we even joke about perverted things about eachother, we went on a band trip to disney world and we joked about how wed all go skinny dipping with our friends, but the one thing preventing this fairy tale i know him too well, its like doing my brother if he texted me right now and poured his feelings asked me out i would loose it. But i dont want my feelings to interfere with other relationships. Help!