Families who care for relatives with dementia in their own homes stand to benefit from a health ombudsman's decision.
Barbara Pointon complained to the ombudsman after local officials decided that the 24-hour seven-day attention she gave her husband Malcolm was not nursing care, so it would not be funded when she took a rest.
She won the case, which suggests that the health authorities will have to review the divide between nursing and personal or psychological care.
The Pointons will receive £1,000-worth of care a week.
The Alzheimer's Society said the ruling had implications for thousands of people living at home or in care homes.
Mrs Pointon has spent much of the past 12 years caring for her husband, who was diagnosed in December 1991. Both took early retirement from music lecturing jobs at Homerton College in Cambridge.
The social services department pays for two live-in care assistants, working alternate weeks, at their home near Thriplow in Cambridgeshire, but Mrs Pointon said her husband needed the attention of two people for 24 hours - meaning she too was always on call.
She took a break one week in five, but had to pay more than £400 a time for another care assistant. She was told this could not be covered by the NHS as she was not offering nursing care, because she was not a qualified nurse.
"The NHS has a mindset that NHS care can only be provided in a nursing home or hospital," she said. "The ombudsman's report blows that wide open".
Sally Hind, chief executive of South Cambridgeshire primary care trust, said professional opinion on whether Mr Pointon's needs met the criteria for fully funded NHS care had differed.