Onlookers said the star appeared thinner than ever as she performed at the End Of Summer Ball in London's Berkeley Square, reports the Daily Mail.
The 25-year-old is said to have ruined god-daughter Dionne Bromfield's singing debut and lashed out at a photographer before collapsing and saying: "Life can't go on. I can't do this anymore."
A source said: "It was tragic, she seemed totally wasted. She was jumping all over Dionne as the poor girl tried to sing for the crowd. Amy didn't really sing a single note, it sounded more like she was grunting down the mic.
"Amy was then asked to pose for the event’s official photographer, but flipped and tried to headbutt him. She looked like a woman possessed. Amy collapsed backstage in tears. She kept saying 'Life can’t go on, I can’t do this'."
Among the 850 guests at the event were Kate Middleton's younger sister Pippa, Sugababe Heidi Range, model Emma Noble and former Atomic Kitten Liz McClarnon.
Winehouse's family reportedly hope that the early release of her husband Blake Fielder-Civil from prison could bring some normality back into her life.
Fielder-Civil is thought to have agreed to move back to his mum's Lincolnshire home, where he will wear an electronic tag and have to abide by a strict 7pm curfew.