Max -
Sorry for your loss and that you had to find us here at SI.
I understand some of your pain — my wife planned to take the secret of her A to her grave, but 18-years after it all, she changed her mind and confessed.
First off, you are exactly right, it does NOT matter how long ago the A was, the pain is new and very real.
Your anger is righteous and well earned.
The reality of your M doesn’t match what you thought it was, but it does not make your life a lie.
You loved your wife with the best information you had at the time and honored your end of the deal.
As to why my wife did not tell me — it was primarily to avoid hurting me — or at least that was her best rationalization.
Cheating is universally wrong, so people who make that choice tend to come up with series of rationalizations to make their choices make sense.
You know she stayed, and you know she didn’t want to hurt you with the truth.
The rest of it she can no longer explain or apologize for, and that adds to the pain in the now.
The endless questions and what ifs you had for survivors guilt are very similar to surviving an A.
Both the accident and the A are not your fault.
A’s happen mostly due to the WS and their inability to value themselves or cope or in need of external validation in an unhealthy way.
If your psychiatrist helped at all with the loss, maybe visit them again to help you start to heal from discovering the A.