At the end of the film, Joe tells Kirsten he had been sober all over a year. When Kirsten is on the way to Joe's house, you can see the lights of a big BAR sign in the same street. It may heavily imply that Joe really proposed to be sober by living near the temptation to proof himself.
The Addiction Displacement of smoking instead of alcohol. The fact that to have to fill your alcohol addiction with another potentially harmful drug like cigarettes.
