Advice PLEAK!!!!

Hiiiiii, i haven't been online in a while but i need advice, ilike one of my mates but im not sure he likes me, he was really flirty with me and still is but hes also flirty with all his mates, he wont tell me his crush but i know his sibling knows and whever i brought up my ex he soon after brings up his old crush but im not sure if its him showing sympathy or being jelly, if anyone has advice please message (*´ ˘ `*) i wanna be sure he likes me or not so i dont get my hopes up (ﾉ≧ڡ≦)｡