Amy Winehouse

Many singers/musicians have messed themselves up on drugs, sorted themselves out and went onto have successful careers, such as Ray Charles, Steve Tyler and The Rolling Stones.
Mary J. Blige is a good example. She was also booed off stage when she was wasted on a British tour and after getting clean she has gone on to make some good, more mature, music.
She still apologises to the crowd when she comes over here on tour for the state she was in ~15 years ago.

To get clean (and stay clean) the addict has to want to. If you don't want to, you use your talent to write a song like Rehab mocking friend's and family's attempts to help you.