"No one has ever raised that curtain since. I have lifted it for a moment, even in this narrative, with a reluctant hand, and dropped it gladly."

Charles Dickens concealed much of his childhood experience from his own wife and children. Dickens' friend and biographer, John Forster, explained that it was only an accidental question in 1847 that prompted Dickens to confide in him. 

You can read the biography in full here.