Well, as I've said, I did know a situation like this and I don't think anybody did judge, although there was a bit of 'wages! Good for you!' attitude towards the man.
What concerns me here is not the relationship as such but rather as I've said the way the immediate position is to sympathise with and dare I say fawn over the man a bit.
I recognise I am guilty of taking the thread off course a bit. But I've noticed this so many times! My mum died when I was a teenager - yes, it was terrible for my dad but I don't remember one person saying 'poor Gingers mum, dying so young.' I barely remember anyone sympathising with me! It was all my poor dad, how would he cope, how awful to lose his wife. And of course when he got together with another woman one month later it was good for him, can't expect men to be all alone can you.
Now here, out of the two, I'd say the man gets the better deal. He keeps control over his life, legs and bowels, stay married AND have a mistress AND still lap up the sympathy.
Would a woman with a 'friend' be treated with such sympathy?
I know women who have dedicated years to caring for husbands with early dementia, with paralysis and other unpleasant conditions, some of which I don't even know the name of, often at home and sometimes for elderly parents too, without a murmur of complaint, yet without the outpouring of sympathy I've seen on here and without having affairs either, they manage to go to village fetes alone, fancy that
Despite that slightly sardonic strike through I DON'T judge, but I do think we need to move away from a single man of a certain age being an automatic subject of pity.