With all honesty your friend may be lying; before you do anything you have to find out if she is being honest, other than that the flirting is simple, say hi to him, talk to him, if there is a spark then it will all fall into place.
Flirt back and make him want you.
go over to him and flirt
Go with the answer i told you earlier,Flirt with her :)
he might like another girl but he doesn't have to marry her you can still have a chance because he can change his mind. you can flirt you can tell him or you can have a friend tell him.
then you must really like him and if he stayed on that long with you then he must really like you too.
it means hes a flirt and he just likes to make you think that he likes you when really he thinks your ugly
you should try to tell him that no body in the will like him like you.
and also to add from the question above he has told you he does not really like his girlfriend
Heck yea!
well theres 2 ways you can look at this, first you could talk to this girl and find out why she will allowe you to flirt with her and flirt back but does not like you the same way, or if you just like it now when u guys flirt dont do anything about it and wait awhile and maybe she'll come around
tell her that you want to be just friends, then flirt with her loads and loads
Sit out the drama. There is really not much you can do here.