Former nun Oonagh Shanley-Toffolo has led an eclectic spiritual life, as Arminta Wallace discovers.

She dresses like a fashion designer and talks like a nun - and at the age of 72 she has written a memoir which, more than most, deserves the title of "life story". Oonagh Shanley-Toffolo grew up in Leitrim in the 1930s. She became a nun at 16, trained as a nurse and was sent to India to care for the elderly, working alongside Mother Teresa in the slums of Calcutta. She became ill herself, was diagnosed with bowel cancer and given six months to live.

That was 40 years ago. Since then she has nursed the Duke of Windsor, married, studied acupuncture in China and been photographed by Lord Snowdon. Oh, and did I mention her friendship with Princess Diana? In person Shanley-Toffolo is bird-like - petite, polite, her conversation punctuated by totally unselfconscious references to matters which, one can only assume, are rarely discussed in the dining-room of the Shelbourne Hotel nowadays: magic, fairies, love and God.

It all began, she says, with her father - a farmer "with a diverse curiosity". He went to evening classes to learn cabinet-making and basket-weaving, he enjoyed buying books and china at auctions - but more than anything, he was interested in the natural world and in what we now call alternative medicine. In those days, it was a furtive business, a world of mumbled incantations and secret potions: iodine for cuts and dog bites, a pinch of ginger in hot milk with a teaspoonful of brandy for a cold, poultices of heated carbolic soap and sugar solution for painful swellings.

The Shanley family rarely had recourse to the doctor, and young Oonagh's subsequent career as a healer was inspired by her father's interest in the healing arts. Nevertheless, her decision to join an order of French nuns while in her mid-teens led to a complete break; apart from a brief meeting when she took her final vows, she never saw her father again. "It was a totally monastic life, and I loved it," she says of her startlingly swift plunge into religion. Besides, there was such a lot to do - there was French to learn, theology to study, people to look after.

The young nuns also faced some unexpected challenges at times of retreat - from visiting priests. In her book, Shanley-Toffolo describes how one retreat master made a grab for her, and how she decided not to complain "lest he be sent away or get a bad reputation with his bishop".

In the light of what we now know about what some Catholic priests were getting up to behind closed doors, does she regret her silence? She shakes her head. "I couldn't see why I should. There were just three instances in 20 years - that's not a lot, is it? And those men might have lost a parent or needed comfort or just needed to talk about - I don't know what." Since she never came across a child abuser, she says, she's not equipped to comment on the subject. "I think it's very un- Christian to write about something one hasn't actually lived."

Shanley-Toffolo loved India, where she went in 1958, but the work was physically tough and emotionally draining. The nuns depended on alms to raise funds, and spent their days begging until darkness enveloped the fetid streets of Bombay. In Calcutta, things were even worse, and though she acknowledges the heroic efforts of the colleague who would later form her own order and become known to the world as Mother Teresa - one of the most moving stories in the book describes the latter's attempt to give dignity to a dying woman - Shanley-Toffolo was bothered by the way the religious orders focused on the elderly - to the detriment, she felt, of mothers and babies. "It seemed," she writes with unusual sharpness, "that women and babies were being left to perish."

Meanwhile, her own health was deteriorating, and she was told she would have to return to Europe for treatment; a verdict many women would have greeted with relief, but not Shanley-Toffolo. "I would have preferred death. Once I observed a funny incident when a messenger delivering a large sack of meat was suddenly swooped upon by a vulture, and his parcel of meat disappeared into the air. I'm sure the vulture's hungry family had a feast. I would have been happy to end as such a meal and give the birds a treat . . ." It was not to be.

Disillusioned by in-fighting in the convent and bolstered by her newfound interest in midwifery, Shanley-Toffolo wrote to the Pope for permission to leave the congregation on the grounds of ill health. Within six months she was enrolled at a London maternity hospital, tearing around to deliver babies on her bicycle - "proof that if you are ill, the best remedy is to study something new", as she puts it. The following year, she met the man she would eventually marry, Joseph Toffolo.

THE wedding date was the same as the one on which she had taken her religious vows - the feast of Mary Immaculate, December 8th - a choice which might strike some people as contradictory, even perverse. "Oh, no," Shanley-Toffolo declares, with a beatific smile, "it's one and the same. You know, if you see God within yourself, you see Him in your partner. To me loving anybody, whether a child, a man or a woman, it's all equal to the love that Christ asked us to give to other people. Love your neighbour as yourself - that's a tall order, isn't it?"

Written in strikingly simple prose, Oonagh Shanley-Toffolo's book is a roller-coaster read. On page 60, she is seriously ill in a convent in Autun; on page 90, while she is having lunch with friends, she receives a phone call from the woman who is now her boss, the matron of the American Hospital in Paris. "Miss Shanley, would you come immediately to take care of the Duke of Windsor? He's to be admitted at 6 p.m. for an operation in the morning . . ." Reluctant to break up a good lunch, Shanley-Toffolo demurred.

"But, Matron, you know I am Irish, and perhaps we shall not get along together . . ." Matron would have none of it, and the Irishwoman nursed the former King of England until his death three months later from cancer of the throat. "My time with him was short, but he impressed me a good deal," she says. "He was an extremely independent man, and extremely modest. His humility was unbelievable. And his whole world was Wallis."

Shanley-Toffolo's portrait of the Duke is at variance with that of history. So is her portrait of Princess Diana, positive despite the fact that she eventually fell victim to Diana's paranoia and was banished for a perceived "betrayal".

People will read her book, she knows, for details of these celebrities. But she hopes it will also, in its emphasis on spiritual and physical healing - and in its trenchant criticisms of conventional medical practice - be a source of inspiration. We have forgotten how to heal ourselves, she says - but it's not too late to relearn. "Medicine in the West is deteriorating, and not just from lack of money. There are many wonderful doctors, but there's not enough caring. Sick people don't need screens and televisions. They need silence - and a nurse who has time to sit down and hold their hand."

The Voice of Silence, by Oonagh Shanley-Toffolo, is published by Rider at £9.99 sterling