Hmmmmmm......
I believe in open relationships, so long as it is a MUTUAL desire.
Armychic....I've been following your posts, (responded a couple times).
You are definately in a difficult situation, and my heart to you.
I think it's fairly safe to say that it sounds as though your gf may want her cake and eat it too. Just from the tactic of hers, it shows that she is into her own self with little regard to how you are dealing with all of this.
Agreeing to an open relationship in order to hang onto your relationship with her is not the answer, as it seems you are merely settling for this request of hers. This will deliver you much heartache in the long run.
I still feel that she needs to ease up some with all this needed freedom of hers and wait for your return so that you BOTH can address this face to face. If she continues to insists upon this "open"ness of hers, (primarily and conveniently for herself), then perhaps it's in your best interest to provide just that....freedom...but for the both of you. (For her to be who she feels she needs to be, and for you to begin your process of healing and the opportunity to find someone more suited for you).
I'm sorry this is so hurtful for you.
I wish you the best. We are all here for you.

Remain in touch.
Shangrala