The 27-year-old had apparently quit alcohol three weeks before she was found dead on Saturday, and her loved-ones think the effects of stopping completely may have been too much for her body.
A source told The Sun: 'Abstinence gave her body such a fright they thought it was eventually the cause of her death.'
And talking about dad Mitch's eulogy at her funeral on Tuesday, the insider added, 'He said doctors had told Amy to gradually reduce her intake of alcohol and to avoid bingeing at all costs. Amy told him she couldn't do that. It was all or nothing and she gave up completely.
'Mitch said the shock of giving up, after everything she had been through over a bad few years, was just too much for her to take.'
A post mortem proved to be inconclusive and the results of toxicology reports will not be ready for several weeks.