When Jeanne became increasingly forgetful, Brian simply put it down to the ageing process. Gradually it occurred to him that it could be dementia, that it might be the onset of Alzheimer's disease. He acquired one or two books on Alzheimer's - just in case.

They were helpful but he realised that Jeanne's condition had significant differences. In particular, it was hugely variable, sometimes by the minute.

He searched the internet for other conditions that related more accurately to her signs and symptoms which, by then, included paranoid delusions - particularly against himself. Anything that seemed relevant was referred to the medical profession. It was mainly the paranoia that confirmed the diagnosis of Lewy Body Dementia.

Brian searched for a book that would help him understand her condition more thoroughly, and how it might develop. None was forthcoming.

If you find yourself in a similar position - he has written this book for you.