I don't always love quotes/advice about not expecting things from people. Because in some ways you should expect things from people. I want my spouse to expect things from me.
Obviously the line isn't meant in a fully literal sense. You expect your spouse to wake up in the morning, do her job etc...
It is referring to the extra things in life/marriage. (And with that attitude you can appreciate those things so much more.)
@jj
Why do I think you're not married?
Possibly because I have expressed this fact on this forum? Or because I am an idealist. But as I said to sky121 as with everything in life use common sense to understand what the real meaning was on that line... Feel free to disagree.