How to tell the bestfriend of the same gender that i wana have sex with him in term of romance. i loved him?

Im in love madly with my bestfriend. I have told him previously that i loved him not only in terms of frenship wise but more than that. I told him that im atracted and i guess i might b bisexual coz i do love a gal n same time my oni bestfriend. He is my 7year bestfriend and i dont wish to be unsincere with him.I told him so that i wont cheat him in our relation. And he took it casually. But wen days goes by after 1 year, im desperately wanted to have romance with him. How am i suppose to day willingly from him? Im geting metally ill coz that. I called him let go out for one night & get drank but he said at first ok but later on he said letz have a geng to go with. Im so cluelesss. Any idea hw? He seems to be a straight guy but i dont know he might be hiding from me.....