I just happened to watch this last night (I wasn't actively looking for an addiction film) and thought it was great. It's the story of Chris Herren who was a high school and college basketball star and played in the NBA. During that time he also became an alcoholic and drug addict which eventually ruined his career (and almost killed him). You can find it by searching "Chris Herren Unguarded" on google or YouTube (also on Vimeo). It was a "30 for 30" film that aired on ESPN.