Mournful Stories

I was watching the last Harry Potter movie last night, and of course people died, naturally that fact made it sad.  So after I had dwelled on the terrible deaths of my imaginary friends for awhile, I began to think of some sad books I have read before.  And I asked myself the question, what is the saddest book I have ever read?  The first book which came to mind was Ever After by Karen Kingsbury.  I didn't even read the whole thing, I just skipped to the last part, and mourned for the characters.  But since I didn't read all of it, it doesn't count.  So to answer the question, the saddest book I've read is Mockingjay by Suzanne Collins.  Everything by the end of the book was terrible.  Many people died, and the main character was forever affected by the war in a terrible way.  If you don't cry while reading that book, I'm sorry, but you have no soul.  So, now I would like to ask you this same question:

What is the saddest book you have ever read?