If my theory is correct, then everything that are in both story lines is because The Stranger saw them in Storybrook and included them in the fairy tales. As far as the queen killing the sheriff by squeezing his heart goes, I’m not saying there isn’t anything magical going on in Storybrook, which could explain the existence of the book before it was written.
I also think that if the book was based on the citizens of Storybrook, that would explain why Henry is seeing the similarities between the citizens and the characters in the book.
Like I said, this theory is just something that popped into my head and I wanted to throw it out there to see what the reaction is. I know it’s got to be full of wholes.