Not sure what anyone else thinks, but I wouldn't mention anything to your W about the snooping or what you know. This will only serve to justify her actions by proving to her that YOU are doing something wrong, betraying her. If you look at the affairees as two people in immature states of mind, then by "proving" yourself a common enemy you give them something to bond over and this will serve only to strengthen their relationship.
Also, this kind of approach (voicing your emotions) has the potential to turn the conversation into a battle over whose feelings are more important, because they are both at odds here. I think that detachment is critical here. You understand that this road you are headed down is painful, but you want to work through it despite this. You own your behavior and it is up to you not to behave in a passive-aggressive way – whether you involve her or not. It's difficult, to say the least, but you can do this. Vent here, or to trusted friends. I've even found that letting loose a primal scream every now and again in the car helps to let that bottled up energy out. Your emotions are important, but not to someone in an EA. Keep in mind that you are doing what you are doing for the greater good of your family while your W is in a very selfish place. Once she has moved beyond this, your feelings will be relevant.
You have already voiced your perspective on the A, and she is aware of it. The only thing that will make you feel better if you talk about it is if she were to agree to end it - and that's not going to happen. You have no control here – the only thing you can do is to make it last longer. I think of this whole process as a kind of Zen-like one where you have to give up all attempts to control the situation or your W in order to have control when you need it. If you are consumed with your futile attempts at manipulating or controlling the situation then you will miss the critical opportunity when it arises.
Just my opinions here, hope they’re of some value.
“No problem can be solved from the same level of consciousness that created it. ” – Albert Einstein
