"The "maybe she's happy with this reality" is by far the least plausible scenario"
Apparently some patients with terminal cancer choose only to know the immediate treatment plans and not the prognosis, because….they just don't want to know. It may be true that she is happy enough in her marriage without knowing the details of his affairs. Some people live like that. And are entitled to carry on living like that, if they want to.
And sometimes life isn't simple. My aunt cheated on my uncle. She confessed. He then volunteered that he'd had an affair seven years earlier. She slowly broke down over two or three years, thinking about my uncles affair. She committed suicide. My parents opinion remains that he should have stayed quiet. This mans wife is apparently not always in good mental health. She's had a number of breakdowns in the past. What state of mind will she be in at a point I chose to come to forward?
Also, if this leads to a divorce, he's made it clear that he would be devastated / destroyed. Obviously the kids would be too. His business would go under since its funded by in-laws and friends, and everyone involved would suffer.
So one thing I know for sure is that I definitely won't be FORCING the truth on her. To me, if it's correct that she has a right to know, she most definitely also has a right NOT to know as well.
And I do believe that, deep down, she knows what her husband does. If nothing else, she knows he's been capable of it at least three times before. Apparently she's made comments about him going "off to see his girlfriend" (he actually was, but didn't confirm this). Apparently she can intuit which are his genuine business trips and which are his affair trips, and ring / not ring him in the evenings appropriately. If that's right, and ignorance is bliss, she can delete my message. But it's a *chance* to know the truth & details, if she wants to.
If she knows nothing, or reality is different and she's just waiting to catch him one last time (for example) then I'm coming forward with new / useful information
She also may believe she is consenting to one thing (primarily sexual affairs, or short term affairs, or ONSs). But it also plays on me that what this man was looking for when he met me was a long term mistress. He didn't carry on looking after our affair (no excuses for him, I just think what he went through emotionally in our affair put him off). Now he's decided he does in fact still want that and has gone back to the search. Now, yes, that's their business alone *IF* his wife consents. But, to me at least, having a permanent mistress on-hand in a nearby location for decades… it seems incredibly serious. And potentially heartbreaking for her. What if she wakes up in 20 years time and realises what he's done. Or after he's died, that their life was a lie, and she never gets to talk to him about the truth. But then again, am I the one to force this information on her?? But am I really forcing her by offering her the chance to have this information???
I posted on another, general forum. The advice there was split 27/8 in favour of NOT telling. The most genuine reason that I could grasp that people cited was that it would make no difference as the main reason, since he's been caught before and she knows he's a serial cheat (I guess they think I'll cause her pain by giving her information she essentially already knows and, essentially, rubbing it in her face). They also assumed a malicious motive on my part which, in their opinion, automatically invalidated any good at all in me coming forward. I was also repeatedly told to "move on" - which is obviously right for me, but maybe not for her (I can see much more of an argument for this if it was a onetime thing on his side, and he indends now to be a faithful husband - but the very opposite seems to be the case). I also have one friend (cheated on) who says definitely yes tell, one (cheated on) who doesn't know, and another (not cheated on) says definitely no.
Thanks for everyones comments on here. And the consensus here by people who have experienced this is so helpful. Not positing this piece (necessarily) looking for more - just helps me to think this through.