How can i get over a guy ive liked for ages?

so there was this guy, leo. ive liked him for over three years! we were friends, and would talk all the time! until last yr, when this loser named justin who KNEW i had the biggest crush on leo, told me that leo said that he liked me. ever since then, leo would act strange around me..he would only talk to me sometimes or if i would try to talk to him he would rush off or whatever.but i would sorta ignore him too, since i thot he was ignoring me. anyway, school ended but we would still text over the summer. until he stopped texting me back. and when i finally asked on fb if he was mad at he, he said no why? and i said well cause u havent been txting me back, and hes like, "well sorry, i kinda have some bad news tho i'm going to schs". and i was like o really? why arent u coming back? and he didnt even respond! and ever since...he quit responding some more. then school started and he got a gf. who broke up w her bf and 3 days later they started going out. she was blond and looked like a tramp! anyway, i texted him again and he said he was sorry if he hadnt been answering me, and we were txting & i told him that i had sorta liked him when justin said what he said, but it didnt matter now and all he said was "oookkk sorry bout that ill see ya around" and when i asked if he had ever liked me he didnt answer. a few days later him and his gf broke up! and right after i found out, i texted him & he actually responded that time! and so on fb i decided to ask if he had ever liked me & he wouldnt hurt my feelings...he said "na i really like u as a friend cause im not really dating anyone cause my last relationship didnt go so good". and he also said that justin was just saying all that stuff about his liking me...etc...and again hes stopped responding, until i called him out again, and this time he called me, apologized again, never gave the reason why hes doing this..and hes doing it yet again! i thought we were friends its like he doesnt even care! how can i stop liking him?