I have a similar experience with my wife. I was so afraid to tell her I started again, thought for sure she would leave! Coming clean was the best thing, not having to hide or lie. Making sure you delete your history on the internet, or checking your pockets, stupid stuff like that. It was THE BEST thing for me and was very liberating. Giant Gorilla off my back, as they say. I think you should sit down and have a heart to heart, show some emotion. She'll see how scared and ashamed you are (I sure as hell was) and may respond well to that. Only one way to find out, but I think you need to do it.