Dear Huan Yi,
For whom? Doesn't seem to bother some folks, does it? And it scoops rhe heart out of others. I'd think that if you had a solid pair bond with your partner, it'd pretty much run to the latter, and if your bond were more based on power and monry, you'd be in a situation where you'd adapt to the first. Lot's of those marriages around and many of them are political. As long as there's still lots of that joy juice running, I'd think that adultery would be more about threats to the power distribution in the relastionship than it would be about betrayals of love; though if everybody was very very lucky, love would be a factor there, too.
That'd make it tough for politicaL marriages to break up while there's still some of that power junk for one person or the other to use. In love marches, you hear the occasional, "Please, dear, not in front of the children!" while I can almost hear the equivalent sotto voce "Darling, let's not do this in front of the voters." I find the thought amusing, anyway, though my wife frequently thinks I'm a cheap date. A few thoughts, anyway, BobK.