What is the theme in Requiem for a Dream: A Novel by Hubert Selby?

Addiction and denial are both themes that connect with each other in the story. Addiction in this novel feeds off of denial leading each of the characters further away from empowerment over the habit. For Tyrone and Harry, denial makes them believe that they don't have a problem with drugs. "They realized they didn't have to sweat it so they dipped a little more into the merchandise. They didn't have to get worried about being strung out when they were the connection, not that that was a real problem. They knew they could stop at any time they wanted to. If they should ever want to." (146) The point of denial serves as a crossroad every time the characters move into a new level of addiction.