Don't move toward forgiveness for a while yet. The results of her actions will not be fully known for some time. Quick forgiveness at this stage will likely serve more as an enabling behavior than a healing one.
She has betrayed your trust and your marriage. It is very unlikely that she has any idea of the full ramifications of her actions.
Don't be surprised if she makes up an excuse not to come home tonight, or if she states that she wants an immediate separation.
She will most likely attempt to pick a fight with you. Don't do it.
If she tells you that she wants a divorce, and for the two of you to just be friends, tell her that you have no intention of divorcing her, nor do you have any intention of being her friend after a divorce. If she wants a divorce, then she will have to do the work.
Don't tell her that anyone is coaching you. Don't reveal to her the source of any knowledge that you gain regarding the affair. You are now in a battle to recover your marriage. A general never reveals the source of his intelligence. I assume that you will continue to snoop until the affair is obviously over after she has made such a claim, or until such time as the relationship is no longer of importance to you.
Once you have hard evidence of the affair, should she remain unrepentant, then there is no longer any reason to snoop.
If your wife should turn out to be in the small percentage of spouses that stop their behavior immediately upon discovery, then you will need a different plan of action, a plan for recovery. We can discuss that at the appropriate time.
All the best, -NOPkins-
I will ferret out an affair at any opportunity.
-An affair is the embodiment of entitlement, fueled by resentment and lack of respect. -An infidel will remain unreachable so long as their sense of entitlement exceeds their ability to reason.