Death's Edge oleh S. B. Sebrick

Everyone in my village is crazy. They whisper behind my back about a brother I've never had. How can they all remember a boy who I know never existed? Sure, my nightmares are a little too vivid. The sight of blood terrifies me, but lots of people can't stand the stuff. There's nothing wrong with me. I'm totally sane. That's what I believed, at least.

Until the night of the earthquake.
Until I saw that broken corpse lying in the rubble.
Until I met him.