Amy Winehouse's family believe her decision to stop drinking may have contributed to her death.
Her father Mitch told mourners at her funeral that he thought his daughter struggled to deal with the sudden withdrawal.
In his eulogy at her funeral service at Edgwarebury Cemetery in north London, Mr Winehouse said she had recently "just completed three weeks of abstinence", adding that she told him: "Dad I've had enough of drinking, I can't stand the look on your and the family's faces anymore."
Earlier this week police revealed they will have to wait up to four weeks for the results of toxicology tests to establish her cause of death.
A post-mortem examination proved inconclusive and an inquest was opened and adjourned with no cause of death given.
Because of Amy's battles with drink and drugs, news of her death was quickly followed by suggestions it could be related to one or the other.
The singer was making plans to record a jazz album and wanted to learn how to play a musical instrument according to a recent interview.
She told the Daily Telegraph: "I would love to study guitar or trumpet. I can play a lot of different instruments adequately but nothing really well. If you play an instrument, it makes you a better singer. The more you play, the better you sing, the more you sing, the better you play."
The 27-year-old star gave the interview while recording a duet in the studio with Tony Bennett.
Amy also confided: "I'm not a natural born performer. I'm a natural singer, but I'm quite shy, really... But then the minute you go on stage, everything's OK. The minute you start singing."