I'd like to address the issue, raised by Heidi, of the man being "all there" with the wife he's with, if I may.
Have any of y'all read the Men are from Mars, Women are from Venus books by John Grey?
One observation he makes is that women tend to emotionally move vertically. By that he means that they're up or down, but always "there".
Men, au contraire, tend to move horizontally. We're closer or further away, there or remote, in or out of our mental cave, however one wants to look at it.
He describes men as often withdrawing into our mental cave to think things through and work them out before emerging to share the results of our ruminations. To us, this is perfectly natural. To a woman, it can feel durn lonely -- "Where on earth did he GO? Why? Get back out here and TALK to me! I'm RIGHT HERE! Don't you love me? Don't you care?" Mars vs Venus!
On the one hand, this situation provides one of the beauties of PM. If he's off being true to his nature inside his own head trying to deal with "stuff", a second wife, whether up or down, is still "there" for company.
On the other hand, PM provides a new opportunity to feel slighted. "Is he off, in his mind, with HER? When it's MY time? And I'm RIGHT HERE?"
Of course that's not only limited to actual PM situations. Any wife can wonder if he's thinking about a former wife, former girlfriend, cute new choir member, whatever. Especially if she asks him "What is wrong?" and he mumbles, "Nothing".
Solution? I think it has to start by imputing to our partners a "good heart".
Wives, who need to feel loved above all, impute a loving heart to him, and start by assuming that if he's mentally off in a cave somewhere, it is not a byproduct of dissatisfaction with your own sweet self, nor fascination with another. Unless, of course, you've been ragging on him about something, which will likely have him feeling like his most overwhelming need, for respect, has just been stomped. In which case, he may well be praying, "Oh, God! Would you please just get me OUT of here honorably?!"
Hubbies, who need to feel respected above all else, (Wives, ever have your husband say during an argument, "I could live with someone who respected but didn't love me lots easier than I can stand living with someone who loves but doesn't respect me"? Did you stand there with your eyes crossing, going "Huh?" It is a commonly stated male sentiment! Mars vs Venus!) impute a respectful heart to her. If you gotta stay in your cave working something out, it won't hurt to pop out long enough to say, "Sorry, Sweetie! I'm just working something out back here in my cave. Sorry I'm not too 'here' right now. But I'm awful glad you're with me despite my preoccupation. I'll tell you all about it as soon as I get it figured out." That's loving, and easier to do if you understand that her request to know what you are thinking about isn't motivated by disrespect at all!
I suspect a wife might, in that scenario, still feel loved, and valued, and say something like, "Ok. Let's sit here and watch a movie together while you think. Snuggling and just being together is good!" Which would probably leave us fellas feeling so respected, we might even open up and talk a bit more as we work it out ... Which would feel even better and more re-assuring to our wives, which in turn ...
Or, at least, hopefully that is what is going on ... *grin*