how can i confront her?

i'm really worried about my friend.

she's been dating this guy, justin, for almost three months, and seems pretty crazy about him...

well, if you don't count the fact that she flirts with just about any guy close within her reach.

in fact, in gym one day, she was texting several boys flirty text messages, and when her phone would buzz, a girl would ask "who keeps texting you?"

and each time, it would be a different guy's name.

she keeps denying her feelings for all of them.

david is "just a friend".

jonathon is "like a brother".

clint is "too old for me".

when i ask her why she isn't talking to HER BOYFRIEND,

she just says "he's probably busy."

i don't really like the guy she's dating, but i can't help but feel bad for him, because he doesn't know about any of this.

i care a lot for my friend and her reputation.

how do i tell her she's getting herself into something bad without her getting angry with me...or denying it?!

help, before it gets worse!