Yes I totally agree about the milk (I mean that is the way I operate). If I want something done I do it. I do it for myself. I don't build up a bunch of resentment etc.
But for the bigger issues, like bringing up children, maintaining a household, financial responsibility. Can we do this all alone, absolutely no question but I would hope that the other person would be trustworthy enough to be relied upon.
Then again, this is an alcoholism forum and I guess that is not the prevailing experience.