Do you think i ever cross his mind...we haven't had sex since early early december!?!?!?

i thought we really hit it off in every way. started talking. eventually hooked up..had sex 3 times in one night the first time. we probably had sex about 6 times total. we'd spoon and cuddle all night afterwards. he told me how attracted he is to me, and didn't pressure me to have sex. but then he stopped contacting me out of the blue, after i met all his friends and whatnot. i was confused..turns out he was seeing someone else. got himself a girlfriend :/ i called him back in february just to check if he was alive but the phone convo was a little weird. haven't heard from him since then..we had such a connection though, met totally randomly. ugh. do you think i ever cross his mind or not?? we are friends on facebook as well.