"And this is the caricature of a girl's wavering heart"
It's these moments in stories that make me happy to have read them. It's what sets a good story apart from a great story.
There is no single word for how you feel when the author 'throws back the veil' to show that single element, the foundation if you will, of all the meat and build that is the entire story.
If there were one word that could come close to describing this effect, it would be: Anagnorisis