Listen, it may be that she has danced the line and she really didn't think. She kept is secret so you wouldn't be hurt - but she knew in her heart it was wrong.
The best thing in this situation is to Do Nothing right now. You can not tell her you snooped. You really can't.
The ball is in her court. I don't think any towels should be thrown just yet.
Hugs, honey.
Me 45, H 46, S 23, M 26, Together 30, Bomb 6-2-08, S 6-19-08; H left 12-29-08. H home 12-09, Still MLC in 2012! Me- I have my big girl panties on. Bring it.