Well it depends what you lied to her about. I mean if you cheated on her and stuff, that's going to take a lot longer for her to get over.

And I think the best thing you can do for her is spend as much time as you can with her to prove that you don't want to lose her. And don't forget to call her, and if you feel like you've called her and spent time with her enough, call her that one last time.

I hope that helps you out a little.