I'm not sure I'd count the latter in the phrase "happy with it", though I know in some cases it does boil down to it. In my exceedingly hypothetical case above I think everyone genuinely was at least in the "doesn't mind" camp. As for tolerating it, I've seen that all too much last year, and it just becomes too horrible if they stop tolerating it. Learn from your mistakes, eh?

FWIW I'm 100% behind anyone who's monogamous. You can't make people be able to cope, as much as you might sometimes like to.