The Goldfinch, by Donna Tartt

Theo Decker isn't an angel when the book begins, though he becomes such a generally sympathetic character as the book goes on, it's easy to forget.  In fact, he and his mother are at the Metropolitan Museum the fateful day when his mother is killed in a terrorist bombing because of the least of his misdeeds. He carries a crushing burden of guilt from his time with the wealthy family of a school chum to the time with his father, his time with his kind and giving mentor Hobie, the fine furniture restorer, and his fractured adulthood.  Tartt does the most inventive job I've seen with the unreliable narrative.  Nothing Theo says is untrue, but he neglects to tell the whole story.  So when something completely unexpected is revealed, you feel like everything you thought you knew about Theo and his life is false.