I want to be more than friends :/?

Hello! Theres this guy that i really. really. like. like. a lot. like. as soon as i don't see him he's all i think about and im always so impatient to see him again. it's summer and were both about to be seniors, and we've been friends since freshman year. well, not like clooose close friends but idk. it's hard to explain. we had a class freshman year and we always used to talk cuz he sat right next to me. and now were also on the swim team together and he's lifeguarding right now, while i have two a day practices. the thing is is that im kiiind of friends with his ex. i mean we're not like best best friends, like we never argue/fight, we're always nice to eachother, ya know what i mean? but pretty much, we're friends. so it's kind of awkward like i feel like we both have feelings for eachother but were just kind of like "ohhh.. off limits" but i was friends with him before i was her. we only became friends cuz we were on the swim team together. like at practice everyone says he's alllways in the stands staring at me. and last summer he always used to flirt with me and i liked him then too, but i never showed it just cuz he had a gf. UUUUUGH. but ok. i think i've always had feelings for him since like august of last year, some phases were a lot stronger than others. but like during xmas we hung out with our friends one time and we were just talking in a circle and he came up behind me (came from the kitchen) and started massaging my shoulders and like later that night he was laying on the grass and he was giving me a ride home and i was above him and i waslike i think we need to go now, its late. and he was like what time is it babe and like just looking up at me god i just wanted lay down with him and kiss him!! and inside i was just like OOOOMG <333333. but im wondering, like how do you just break down that friends only barrier? what are your thought on this? i know he's liked me at one point, he might now too. we text, but never just to talk or have a conversatio