Rings true for you? SPOILERS
The final five minutes surely resonates with all men around the age of fifty, although that doesn't rule out women or people at other significant milestones in their lives.
It kind of sneaks up on you since it looks like Penny will live happily ever after with this wonderful woman and a boy with whom he has a real fatherly connection. But he's written himself off as being too set in his ways, too long in the tooth. I suspect it's a common feeling.
So I wonder if my theory holds any water: does the story resonate with you because it rings true with your own life experience?