Talking doesn't help. Beating ass doesn't help. I can name about 30 folks off the top of my head, friends, cousins, uncles.....heroin, meth, coke, crack, whatever...
Those who get out of town clean up. Those who stay in town are as good as dead. Those who get cleaned up and return to town usually relapse. Its sad but true. Hopefully you caught him young enough to make him wise up.
You could always use the piss test and ass beating method. Test his ass every day. Beat him when he fails.