Personally, I'd forgive her. Life is hard and people make mistakes. She will have to live with this one and holding it against here is no good for you or her. However, it would still be time to move on. You can not build a relationship based on this kind of deception and lack of respect. Nowhere does it say you can not forgive her and still move on. It's going to be a life lesson for both of you and hopefully you'll both come away better people for it. Good luck!