Guy troubles :S what do i do with him?

Okk soo i SUPER like this guy and i know that he somewhat likes me at least as a friend for sure because he always tells me he thinks i am amazing and stuff and always talks to me on facebook first or texts me first, well k so i dont know if its his personality or whatever to just be a flirt and be nice to everyone and stuff but i seriously think he somewhat likes me but he has a girl friend and i know he super likes her cuz he told me... but i dont know cuz its like he treats me if shes not there to talk to its like oh ok i am going to just go talk to her than and as soon as she is able to talk to he totally forgets about me :(, i dont know what to do cuz i really think there could be a chance for something to happen between us but i dont wanna wait.... does it sound like he likes me? or should i forget bout hiim? what do i do!