My GF told me that she cheated on me, it hurts badly, but i forgive her, i know that thats in the past, i just hope she wont take advantage of how much i can forgive.
While it's admirable that you're willing to accept her back, you should ask her if she's still interested in you. Either way, I wish you the best of luck, it sounds like a lousy situation.
Infidelity is a serious breach of trust. I don't think I'd be able to trust an unfaithful partner ever again. Better to end the relationship now, if you ask me. Regardless of what you do, however, good luck!