good sex usually leads to good marriages.
guys are simple. i'm one, i know. if you've got a "good guy", his positives way outnumber his negatives, he doesn't get blasted nightly, is a good provider, good solid dad, takes his faith seriously, understands how hard you work at home with the little ones...all those factors are in play, you as the wife gotta keep the sex hot when time permits. i'm a big advocate of the women in relationships keeping themselves fit, keeping themselves involved sexually in the marriage. all too many times a woman will "check out" of the sex & maintenance department with excuses like "the kids wore me out" or "work was a drag" or "housework needs attention", " don't have time for pilates", blah, blah, blah...all at the expense of the marriage. sex for guys is very, very important. that's the "us time" you mention. "us time" usually menas "sex time". you fortify the sex, you fortify the marriage. all other things will take their due course.
now, that being said, don't go nuts on me here. if both of you are exhausted and there's a critical event in your life happening, by all means use common sense. let's say your guy has a big presentation tomorrow at acme law firm and needs to prepare...now isn't the best time to swing your nipples at him. no matter how nice and pert they are...get what i'm saying? lol...good...