At what point does flirting become cheating? Should I be worried? What should I do?

Sorry hun, but you're man doesn't seem commited at all. I mean, if he was, he'd only think of you as the iest girl, and wouldn't be thinking or talking to other chicks like this. It's really not good, and this is border line cheating. If I were you, I'd talk to him about this, it could go bad.