@mrfriendly8181If I ever get around on writing it all (it's necessary huge, but can be tackled in semi-independent fragments, possibly), I have one where...
...she's young, insecure virgin full of issues a somewhat jaded guy pick up in a drawing class... three years later they may or not be married, but she cheats, he is crushed but let her go (possibly mishandling the situation foolishly).
Yet, they remain friends, and soon even become friends with benefits again, albeit very and increasingly infrequent. For several years she cheats on each of her many serial relationships with him, usually signaling impending sudden end of her current active relationship. The club of her ex-es is growing, with him as the chief counsellor who may have prevented a suicide or two.
He has own relationships in the meantime too, including his quite serious attempt to pick up one girl ex abandoned from a lesbian relationship, but despite hopes of all three (the girls too remain friends), he doesn't turn out to be "the magic dick" after all.
Although his quiet hope the ex may eventually return and thus the resulting reluctance to fully commit to anything may have been in way too. And then there's a longstanding but infrequent and kind of accidental D/s with a dancer/escort he has for a 100% discount almost anytime, that gradually becomes his main relationship.
Eventually... the crazy ex swims naked into the sea to be picked up by a loitering superyacht as if by random, leaving her engaged groom and her original ex both (among others) gaping from the beach, but unlike the groom, he realizes knowing it coming. There had been all signs of her next leap, although he has only vague guess who's on the yacht.
And the storm clouds of the sunset they sail into makes him rather pity than envy the guy picking up the mermaid, now an extremely powerful being that's so different from the insecure virgin he picked up all those years ago, and he finds pride in having played role in her nurturing.
I consider to frame all above as his long confessional to said dancer who was present in the act, as he's crushed all anew, but also finally free. Yet quarter of a century later her clothes are still in his country house closet, even though only her name occasionally appearing in coauthors list under academic articles on quantum computing and artificial intelligence are his proofs she's even alive.
But if anything, her adult daughter he never knew existing might rather be who takes advantage of that forever standing invitation to his country house, but that's another story entirely.
But I'm afraid the pigeonholing loving folks would put that down as just some extreme version of "cuck shit" it certainly isn't.
