I think it was simply that there was another person there who could be doing the chore that wasn't done - regardless of standards or expectations of how it be done. When I walk into a kitchen of dirty dishes now, I clean them, no emotions involved, no stress. In the past, I'd walk in, sigh, and count up whether I'd done the dishes more often than my partner or not. He did the same with me, and I remember a bit of that same resentment with college roommates. I think it's just part of sharing living space, and I don't miss it at all. To blame it on men or women or marriage or children is the part that doesn't ring true to me.