Boy drama (kinda long) please help!

there's this boy that i meet and we hit it off well. He would flirt and was always super sweet towards me. He made me feel extremely special and i started catching feelings something i don't do often. I went away for about a week to cheer camp. During that week we lost our "best friends" thing on sc. About 2 weeks later he sent me to go on some girls instagram that posted a picture of him with "my love". The day after that i asked him what are we and he said "im not good enough to be your boyfriend i just wanna be close friends" well that was a lie bc he had a girlfriend. Am i stupid to be upset over him? Am i wrong for wanting to stay close to him? I want to tell him how i feel but i don't know how. Any help?