This sounds like hopeful thinking and it can be, if we understand our strongest position within it. It is not as important to recognize that people change as it is to recognize that our relationships with people change.
An example: ”Will my wife EVER stop complaining about my coming home late?” This is a passive position—change may occur but you don’t have a lot of control over it.
The more active position: Will I EVER accept that my wife’s and my views on dinner/family time are a sacred difference between us; and am I able to take at least a small step toward collaboration, like coming home early one day this week, if only to show her I respect her values?”
Another example: Why is it that the man who made you laugh when you were dating seems these days to be laughing at you? This is contextual. When you were courting, did you rely on him for lightness? Now that you are married with children, do you expect his lightness to turn into the weight and depth for which you now look?
It is helpful to differentiate between changes in our significant other and changes in our requirements of them.
One more example about change in person vs change in perspective: Although it is true that your aggressive, contrarian son may emerge in a few years as a determined, successful student and citizen, you are more in control of changes that can occur in your perspective of your child and his behavior.
Is there lightness to behold? Are there small steps to be taken toward harmony?