Deceived,
Read the below from OK NOW.
Don't automatically expect your marriage to be over when you start laying down your boundaries to your WW. We talked about the need to regain her respect or she won't stop her cheating. You do this by being tough, strong and unyielding
You are in a fight for your marriage and your personal strength will be the determining factor as to whether you succeed or not. If your wife understands that you are really prepared to divorce, you've just about had it up to here with her contempt, and you have really reached the end of the road with her disrespect and blatant cheating, then she may very well back down. You would need to reach a method of accountability so you know what she is doing throughout the day; you might even insist she changes jobs.
Fundamentally you have to approach the showdown with ruthlessness; be prepared to risk all to win. When you threaten divorce, no tears, just a cold, implacable demand that she bends the knee or its all over and you will grind her cheating ass into the ground. Get fucking angry right now and convince yourself with a 100% certainty that you win this confrontation, by either dragging her to the divorce courts, or by her acquiescing in a submissive manner.
You can do this; the power lies with in you to take control of your marriage.
once you see the attorney and GET SOME PAPERS in your possession, you need to get as angry as you have ever been in your life. You need to feel the hurt that you have absorbed every day since this started, all of the crying, all of the pain in your gut, and all of the betrayal.
When you drop your bomb on her head, DO NOT tell her how much you love her and desire to R with her. Tell her she can do whatever she wants to now because YOU have made the decision that you are not living like this anymore.
Personally, in your situation, with as cunning as your wife has been and as weak as you have been, I do not think without a confession from her that you will uncover anything. She is smart enough that she may have a fake e mail or any of the other electronic tricks at her disposal, and since this is occurring at work it makes it even harder.
If she was using a personal laptop for all her games it would be easier because you could if you wanted to just grab it while she was sleeping or out and take it to a Geek Squad or other tech expert to find out what was on it. i guess that would carry legal ramifications with her work computer.
This has come down however to REAL SIMPLE. When you give her divorce papers,if you do it right, she is going to realize the game is up, and she either divorces you or stays married to you.
You WILL get the shitstorm of anger and accusations of your terrible performance as husband and outrage that you do not trust her.
That is all par for the course. EXPECT IT!!!
And in her anger she just may do something stupid like admit everything or run right to her lover or one of them.
You only have 24 hours to attorney appointment. DO NOT let the attorney give you shrink advice. he or she is there to do your bidding and the advice should be legal, financial, etc. The attorney is not an infidelity expert in all likelihood.
Now try to relax, and then start tomorrow morning to think of all the shit you have put up with and what this woman has done to you since this started, and rejoice in the fact that it is going to soon be your turn to start throwing the knockout punches.