u/alaskaliar

If anyone has suggestions for better subreddits to post this please let me know.
Also, please do not judge me, I understand I was wrong and have been forgiven by relevant parties but feel I need to be honest to get the best advice.

Some years ago, I (F) had a brief affair with a married man that then returned home to Canada. We remained in friendly contact via text until very recently.
Earlier this year, I and his wife started receiving emails from a since deleted burner Gmail address and deleted instagram account. Mine simply said I need to contact the wife and provided her contact info. She received information and 'evidence' that did not incriminate the affair, but did lead to him admitting his infidelity. She did engage with the sender, I simply ignored it.
The instagram was used to send 'disappearing' images, and was quickly deleted.
The messages were not threatening, but did become increasingly nasty in an attempt to convince her to leave her husband.
Her and I were in contact for some time, while he and I gave it a rest. During this period I received a WhatsApp message from a random Canadian phone number purporting to be him. I am still on the fence if it was or not, but both he and wife are convinced it was a generated number.
After we both blocked the gmail account, it was quiet for some time but recently I have started receiving sporadic, mean natured messages from Proton emails. I am no longer in contact with the couple so I have no idea if they are too.
Out of frustration, I did reply to the original gmail, which bounced back stating the address does not exist.

I want to find out who the 3rd party culprit is so that I can make it stop. We are all trying to move on and this isn't helpful.
I spoke with local police who essentially said because the messages did not contain threats of harm, libel or blackmail there was nothing they can do.

I contacted a private digital investigator that suggests identifying a deleted gmail would require a court order (and I believe this is the case for Proton, too) - given the police deny any criminality, is there any possible civil avenue I'd have to obtain this?
The PI has quoted $1k per hour just to consult, which I'm not willing to pay if my chances are so low.

I (single, F) had an affair with a married colleague that was only in the country for a short time. I somewhat initiated by flirting while black out drunk at a work function, but he actually initiated further and ongoing contact. I figured it would be a one off fling, he’d go home and we’d move on. Except that we became inseparable. We fell in love.
I did feel guilty, but I’d also heard his wife speaking on the phone and she was legit abusive. We kept telling ourselves we’d end it when he went home, but we kept up via daily phone calls and videos for months.
We eased off into ‘friendship’ territory but continued to text almost daily.
It’s been about 3 years.
Recently, some anonymous person started harrasing both his wife and I via burner accounts with ‘proof’. It wasn’t substantial but he panicked and confessed to her, and she contacted me to ask my version of events.
I wasn’t going to respond, but he said it would help (there’s kids involved) and then fed me a not quite true version that minimised our involvment. He convinced her we’d not spoken for years, then gave her my number.
I just want him to be happy and if that is what he wants, I will abide. So I gave her a watered down version, I took the blame for initiating. She was so kind. She explained why she’d been so horrible at the time. She almost blamed herself and said she’s going to forgive him.
Now I feel so much more shame and guilt for lying for this man than I ever did about the actual affair.
Part of me wants to tell her I lied. Part of me wants to tell him he needs to tell her the whole truth.
Does she deserve to know? Would either option eleviate any of this guilt I have?