1) When you're partway through the book and someone shares a major spoiler.
"You are now my enemy, Alan."
2) Reading so late that you fall into a book-induced stupor.
"Just one more chapter..."
3) Getting up the next morning.
"At least I know what happened to Megan Hipwell."
4) When your friend/roommate/child/significant other/public transit seatmate won't stop interrupting your reading.
"Really, Kenneth? Really?"
5) When the house creaks right at the scariest point of your book.
"It was just the heater. Definitely not a Nazgûl."
6) Reading in bed while wearing glasses.
"There's gotta be a spell for this. Harry Potter never dealt with this nonsense."
7) When your favorite character is sick and doesn't seem to be getting better.
"Beth is really, really sick. Jo's there, but I don't think there's anything she can do."
"You want to put the book in the freezer?"
8) When you get to a feast scene and realize you haven't eaten in ten hours
"I have no idea what Turkish Delight is, but I'd kill for some right now."
9) Trying to make peace with an unexpected ending.
"It's fine. Nothing happened. Old Dan and Little Ann are fine. There's no such thing as mountain lions."
10) When a sticky-fingered friend wants to borrow your book.