Breathe. These things happen more slowly than you think so just breathe and do nothing until you get your bearings again.
Listen to Rick1963, he'll give you very good advice.
Read DB or DR again and see if it really suggested bringing suspected OM over and accusing the two of an affair. That was a really incredibly bad idea. Do you have any proof that there's anything other than a friendship there? No, you don't.
You need to stop snooping on her immediately because it's making you irrational. You need to think about whether an EA or a PA is a dealbreaker for you. Most of us start out saying obviously yes it is, but over time we begin to see how we played a major role in the breakdown of our marriage and the black and white become blurred. We learn empathy and forgiveness and humility. So think about whether it matters before you snoop again.
Tell us what your current situation is. Has your W asked for a divorce? What is good in your marriage, and what is not good? What complaints does your W have about your marriage and about you? Do any of them ring true to you?
An angry spouse will say or think anything to justify getting out of the marriage, so there may be a lot of extra complaints that are just stuffing, but at the essence there is something that is wrong with your marriage and you need to find out where it involves you and fix you.
Others will come with good advice for you. Stay with us, keep posting, tell us more. Try to calm down and don't make things worse.
Adinva 51, S20, S18 M24 total 6/15/11-12/1/12 From IDLY to H moving out 9/15/15-3/7/17 From negotiating SA to final D at age 50 5/8/17-now: New relationship with an old friend __ Happiness is a warm puppy.