RANDOM QUESTION - Can any one woman fulfill 100% of a man's needs?

I knew this man who had a mistress on the side for decades.  His wife never had a clue.  He said his wife lacked affection, lacked interest in his interests, lacked worldly wisdom, and he was never sure whether she had an opinion on anything that mattered to him.  He gave her a lot of free rein to make household decisions, but even on the rare occasions when he put his foot, she clammed up and ignored him, leaving him frustrated.  I don't know the details on what he saw in her in the first place besides her lovely face and slender figure, but he confessed that he didn't really find out what sort of personality or character she had until he retired and was stuck at home to spend time with her.  Thirty+ years married, and turned out she was more or less a stranger to him.

While he was confident that his wife never cheated on him, he needed somewhere to go to get his needs met.  He wasn't willing to abandon his family for reasons I'm not going to share here right now. 

In the end, he loved his wife.  In the end, she loved him.

There are women who bitterly wonder what's in it for the "other woman".  Why be 2nd?  There may be a dozen responses to that, but what's the point in demanding to be the one AND only?  If you cook, clean, take the kids to soccer practice and sleepovers, exercise and stay fit, get waxed in ungodly places, play guitar and whisper sweet nothings with panache, wear lingerie, shop on sportsheets.com, and all that fun stuff - you still can't be enough.  Men like variety.  Cheaters say sex with some women doesn't mean anything to them.  Is that true?  Is it possible to climb into bed with someone without feeling?  It seems so dirty.  If all one needs is physical exertion, won't a trip to the gym do the same thing?  I'm kidding.  It's not the same!

My question then, is can any one woman fulfill 100% of a man's needs, or does a mistress on the side actually do a service to keep marriages together?  If a wife has a roof over her head, never misses a meal, goes on family vacations and has the karats on her left hand, should she demand her husband give up the mistress if she finds out?  Is monogamy even natural to humans?

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