After reading most of the replies here i had to read your post again just to get a grip on situation. Sigh. Anyway, does studying far means you're still able to see her on a weekly basis, at least?

Three strikes and you're out, no? There's a limit to forgiving and fidelity ain't something anyone look lightly upon. Words are cheap, if you have trouble even trusting her then this relationship doesn't look bright at all.

Talk to her, seriously. What does she wants? She's looking for some fun? Is she serious about you?

Then get real about yourself. Can you deal with her flirtatious nature? Obviously not. And tell her what she's doing is hurting you.

Whatever the outcome, this is your relationship and you should have enough logic in that brain of yours whether both of you should patch up or just let go. There's more to life than being a doormat.

that's a lot of wrath stored up inside you.