Again Mr. Flibble, sorry for your pain.
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I write this next section in the hope that maybe there is a betrayed spouse reading this or who will read it, and not fall for the standard cheater's bullshit, and they find the strength, as you did, to get the truth before committing to reconciling with a disloyal liar.
Before you told us there was more, but seemed to be open to a polygraph, I was going to coach you on how to ask questions and get very specific so she had to commit to a given answer that was polygraph-worthy. (I kind of started that already)
Her strategy was to gloss over the details and then try to love-bomb you, pussy-bomb you, and simply keep her head down until you moved on. It almost worked, but I could tell you still had doubts.
And I can tell you something: You would have always had nagging doubts because you didn't get the truth, a story that makes sense.
There is a poster here named Nanatwo who has this in her signature: First the truth. Then, maybe, reconciliation. Louise Penny
To me it was pretty obvious that 1) your wife was holding a lot back, and 2) She was unstable.
That's why I kept hammering at that bullshit story about the car and telling you there was more.
There is always more. Cheaters will lie, minimize, and then they will lie some more. Take that to the bank.
Other people who have been betrayed: Her story was absurd. Adults don't steal off to a private place to just "smooch". And by her own admission she was in the car with him many times other than the one she flagged as "The Session". And she is an adult. The idea that she was shocked at his trying to get under her skirt or whatever is ludicrous.
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Here is why your wife told you what she did yesterday: The threat of a polygraph
She tried to tell you as much as she could, short of sex, which she probably considered to be your ultimate dealbreaker, in the hope that you would believe that she had finally "come clean" by telling you how bad she was and then you would try to work through it with her.
Another thing to understand about cheaters is that they try to decide what your dealbreaker is - how far they can go and when it becomes too much. Then they move those goalposts again and again.
Finally, it becomes: It's okay because my husband/wife doesn't know [dealbreaking act], so this really doesn't hurt them.
***
What makes me really mad about what she has done to you is outside the cheating. That's just normal repugnant behavior. But the fact that she risked the health of her entire family screwing around with this dude during a worldwide pandemic - a guy who was fucking around with at least 4 other women - the risk she was willing to place her family under is off the charts crazy, stupid and selfish!
UGH! I am so sorry for you Mr. Flibble. This breaks my fucking heart.
At the same time, I am relieved that you are not going to spend so much time in the same limbo that so many of us faced, because we didn't find a place like the Surviving Infidelity Just Found Out Forum early enough, or we didn't take the advice from the people who say to demand truth and accountability before offering attempted reconciliation, or instead we took the advice from people who seem to focus more on keeping a couple together as a "win" than what it means when a betrayed spouse continues living with a liar. AKA rugsweeping.
Please get some rest. Please focus on your children and yourself. Then moe forward with your life. You are a good man and you will make through this. It will certainly hurt, but not as bad as living with someone who you know is lying but cannot prove it.
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I hope your wife gets some help. But she needs to truly want that help or it will do her no good at all.
She has to seek help not because of what she lost and hopes to recover, but because of the serious character problems that allowed her to throw it away.