My co-worker liked me & i nvr really payed him attention until a lil later,then i find out he had a GF!?

but i still like him and now he acts different towards me.like he always asking for or he wants to touch me or he wants me to send pictures of me naked.at first he seemed to really like me now it seems like im just some girl to him.he says that he do like me but it doesnt make sense for him to break up with his girlfriend if their having & we're not!and another co-worker told me tht he occasionally flirts w/ her when im not around.what to do plz?i REALLY like him now.ooh and another co-worker tld me tht he said he wnts to break up with his girlfriend but they been together so long & he dnt know how.but the co-worker who said he flirts with her said tht the co-worker who tld me this is the one who got them tlkin;telling her tht he likes HER & he dnt wnt to tlk to me because im a lil girl!!!!HELP PLZ!