I can kind of relate to you. Kind of. I am in a long distance relationship right now with a guy I met online and have not met him face to face yet. And sometimes I catch myself getting flirtt towards friends. Does she talk about her boyfriend a lot? Or do you ask? I would start talking about him and see how she responds. I flirt but it is harmless. And very little. I love my boyfriend but sometimes the distance gets to me and I just do it unknowingly. I would say it is narural though. She is probably craving a closer relationship but may also be confused and fighting herself because of the boyfriend.. I don't really know the stort so I can only say from personal experience.. I hope some of this helps? O.o
Like what $namenotrequired said, she can't flirt w/ her "boyfriend" so she's doing it with you. I mean, she maybe wants to hug and touch w/ her guy but because he's from a long distance, she can't do it w/ him. And since you're w/ her, she finds easier to express what she feels w/ that guy to you instead. Eh? Ahh.. you better confront her to know exactly what she really wants or thinks especially w/ you.
Respect the relationship and tell her it's not cool to do that even though you like her. Don't let her do a stupid thing and cheat. Don't let yourself be cheated with. It could get you hurt, too. Best of luck~
Any girl who is willing to take on other guys when she already has a boyfriend (of course she's got a guy in another sate, makes this behavior even easier), is just bad news. She's obviously got looser morals, so I wouldn't try to get anything from her other then a good time if that's what you're okay with lol.
She's horrible dating material. Trust me. If she's okay doing what she's doing to her boyfriend, I promise she'll do it to you.