While I liked some of the aspects of this book, as a whole it just didn't work for me. Given the generally glowing reviews I have to wonder if we read the same book.
What I enjoyed: The idea of having to figure out the secret no one will talk about, the fairytale interludes, and the way the twist was handled. In regards to the twist(s) I really liked how everything fell into place and it didn't seem like the author was misdirecting you.
What I didn't like how it was done but I felt had potential: The way the amnesia and migraines were handled, the fact that Cady isn't a reliable narrator
What I hated: The characters, I found no likeability in them and while you aren't suppose to like the Sinclairs I didn't even like the Liars. But the biggest thing is that this story isn't new or revolutionary. It reminded me so much of the 2009 film The Uninvited and also Shutter Island. Early on I started associating the book with these two films only to finish the book and find was stupidly similar.
I think what ruined my liking of the book was that:
1) while I enjoyed the ending, I was annoyed at the journey to get there
2) I never connected with or liked the characters
3) everyone has been going on about how this is the best book ever so I had high expectations