A sudden desire to find someone like the love interest in the book.
Slight drooling over certain moments.
Sudden bursts of emotion.
A need to share with the world just how fantastic the book is.
The realization that this book WILL end, eventually. And feeling ridiculously torn.
Extreme comparisons are made between your life and the characters' lives in the book.
Making irregular noises at 3 in the morning because something amazing just happened.