Is he just being nice??

Hi, i really need some opinions. Lets start from beginning. I am Student and working in the uni event venue. I have been putting on events in their since a year and there was one security guy (who is a student too) I liked from beginning on. We dint really talked much to each other just a nice hello and how is it going.

Than 3 months ago I got hired as security aswell and after my first shift he said how good I was and bla. Than a week later it was my birthday and my friends and I where out in at the venue and he was working and he said how amazing I looked. A couple of weeks later I was working at a festival at the uni which went over 3 days. The last day we where working together and talked a lot and got along very well. But still nothing. A week after that we where at a award after party and he was just dancing and chatting with every other girl in this room. He has this wired thing, every time he sees me, he says my name out really enthusiastic – but its just my name he is doing that with. Well a week later we had a staff night out and as im new in the staff group and everyone knows each other I just tried to fit in and dance along. HE was dancing with every girl again, NOT ME. But every other girl. Than he came up to me and said: Oh (My name) I just love you. - in a very excited and probably drunk state. Just out of the blue. So the last thing happened this weekend. I was at a house party where he was too and he saw me smiled and than again said my name is this wired way. 2 other things. He had since ages on Facebook that he is in a relationship but no name behind it and never has anyone mentioned a girlfriend or every other guy who has one brings them along. And the way he is dancing with other girls is definitely not a way a guy should dance with girls if he would have a girlfriend. The other thing is he is on a online dating website, like where it says he is single and looking for a relationship. SO the question is, does he like me at all and what should I do???