Good question, Twila!
Actually, both do.
A good friend of mine said to me once: "I love when people marry each other. They are all like 'I Love You! You're Perfect! Now change.'"
We all do it. We (both sexes) marry the person we love more than all others in the world, all the while looking at them through our rose colored glasses, white picket fences, and romantic ideals. We then set out to change them when we realize that they aren't quite as "perfect" as when we first fell in love.
Expecting our mates to change and for everything to be all rosy, all the time, just because we get married is , my friends, an unrealistic expectation.