It depends whether he's quite an outgoing person and talks to lots of girsl, or whether he seems to actually really like sum1 else. If he's just very flirtacious with everyone, the best advice i can give is to try forget about him. I know its hard, but i speak from experience - if u get even the slightest bit jealous (and lets face it, nearly all of us do) then he'll just break ur heart. Again if he genuinley likes someone else, then theres not too much you can do. Maybe just make sure ur always there for him as a friend - thats how some of the best relationships start! Good luck! cxx