Is Charlie a reliable story teller?

Charlie is reliable as long as the reader realizes his emotional state. Charlie does not try to deceive the reader but he certainly has issues that affect what he tells us. Charlie struggles with apparent mental illness throughout his letters, but he never explicitly addresses this problem - rather, it lurks in the background of many of his accounts. At the conclusion of the novel, it is revealed that Charlie was sexually abused by his Aunt Helen when he was a child, but that he had internalized and concealed the abuse out of his love for her and as a result of his empathy for Aunt Helen's own problems as a child. Charlie's narrative reflects is angst but I don't think he tries to manipulate us.