maybe, 3, 4...10 years down the road some especially divorced betrayed spouses may say "wow, my ex spouse gave me the greatest "gift" of all time by cheating, leaving and divorcing me" however, that's not the way it sounds to a large majority of betrayed spouses in the thick of the most painful thing many will ever experience in their lives. It's NOT a "gift'.
I know you don't like the word, you have made that abundantly clear. And my sich is a little different but ultimately the same.
And oh by the way my relatives were obliterated in the holocaust, I have spent time in a POW mock camp and had commanders that were POW's with John McCain. I so agree that in the thick of this that I thought that my life couldn't get too much worse. Never could even under stand how I could say that it was a gift. There is a saying no PAIN no GAIN. People don't change until the Pain of changing is less than the Pain of staying the same. That is why a wayward person opts for the path of least resistance. It took me a long time to understand that although I had no adultery in my sich that their was still infidelity. And infidelity may mean that no other person was involved.
I unlike you was not able to DO anything other than DETACH and let go, no other person meant NO EXPOSURE or any other tricks.
That all being said I still believe that my ex has given me a gift. I have recovered, thrived and blossomed after the pain subsided. I love and am loved, I am happy and living a full life. My adult children are glad to see me in this recovered state.