It is undoubtedly a mistake to feel you know someone just because you have read the story of their life; despite the artful intimacy of appearance, there is always a considerable distance between person and page.

Even so, sitting down with Isabel Allende feels more like an acquaintance rekindled than a first meeting.

Fragile, delicately pretty with big brown eyes and an elfin face, she perches gracefully on a sofa in the drawing room of the Merrion Hotel and manages to be both disarmingly open and slightly wary. Although, in the course of the interview, she says that she has never regretted her candour -- "I have not done anything that is so awful that I cannot share. I have never tortured anybody. I have never tried to harm anybody on purpose. Other people make the same mistakes, and that is why readers connect with me" -- still there is this gossamer thread of a gap that she is careful to maintain.

Allende's first book, The House of the Spirits, has been translated into 20 languages, after being first rejected by several publishers. Since then she has written 15 more books, and sold well over 50 million copies, taught literature in universities across the world, received a dizzying number of literary and honorary awards, was a flag bearer for Latin America at the Winter Olympics in 2006, and established an eponymous charitable foundation to help women and children escape poverty and ignorance.

Although her novels -- epic, dynastic tales of love, life and death, where the boundaries between "reality" and "fantasy" are unselfconsciously blurred -- have considerable charm and have earned her many devoted fans, it is her two works of non-fiction that have produced the strongest reaction from readers. Even now, 14 years after the publication of Paula, Allende's moving account of the life and tragic early death of her daughter, most of the many letters she receives are from people who have read and been touched by this book.

Allende was born in 1942, into a Chilean diplomatic family. Her cousin, Salvatore Allende founded the Socialist Party of Chile, and was the first ever Marxist president to take power by democratic means. In 1973 he was deposed by General Pinochet's US-backed bloody coup and died violently. Isabel fled to Venezuela with her young family. "I couldn't stand it. I didn't want to live in fear and I didn't want my children to grow up in a place of terror," she says now. "I saw so much violence. Bodies floating in the river, people being arrested and disappearing, friends that came back from torture, thousands and thousands of people that had to leave into exile. There were concentration camps; we knew that they were torturing people in many places. It was a very awful time. Yet on the surface, for a tourist, it would look as if nothing happened." Even now, her greatest fear is violence; "I think it is always present. All kinds of violence -- the institutionalised violence of war and government and police, the many forms of abuse of the stronger against the weak -- women, children, the poor, prisoners -- that is what I fear. My obsession is peace."

Allende now lives in California with Willie, her second husband, surrounded by the "tribe" she has gathered together. It is a sprawling collection of family, friends and in-laws, united into coherence by Allende's need for a clan, a need that she says is "cultural, but in my case exaggerated". Compared with the traditional extended family, this man-made circle is, she says, "better, because you chose them. We are there because we all want to be together. If I was living with my family in Chile, I wouldn't agree with half of them, about politics, religion, family things ... this tribe is what holds me and grounds me."

Allende's latest book, The Sum of Our Days, picks up almost where Paula leaves off, and is a mesmerising account of the almost operatic lives of this extended family, and her attempts to hold them together. The domestic dramas unfold at a furious pace -- after Paula's death comes the saga of Willie's drug-addicted daughter, who gives birth to Sabrina, a severely-ill baby who must be somehow nursed to health, before herself disappearing without trace. Then, Allende's son's marriage breaks up after his wife leaves him for a woman who is Willie's son's fiancee. And these are only the major plotlines; there are troubles between Allende and Willie, problems with the children, disasters facing close friends. Does she think her family are particularly prone to drama? And how, under the circumstances, does she ever find time to write at all? "I think there are soap operas in every family, but not every family has a writer," she responds sagely. "Also, those 400 pages happened in 13 years. It sounds much more dramatic than it was. There were five years where things were pretty bad, when my daughter died and Willie's daughter died, my son went through an awful divorce and it seemed as if we were cursed with the evil eye, but there have been many good things as well."

Scattered through the book are the kind of coincidences -- of people, place and date -- that need and opportunity can seem to transform into miracles. The novels, meanwhile, are rooted within that literary tradition known as magical realism. So does she believe in magic?

"There is a lot of stuff in life and in the world that we cannot explain or control. In the western world we tend to ignore the stuff we cannot explain, but I come from Latin America, and I'm a writer, I see the poetic meaning in things and the connections. Also, I spend a lot of time in silence. Most people live in a hurry and in the noise, so they don't have time to notice anything." Although she has never seen a ghost, this doesn't diminish her respect for the spirit world.

"I believe there is a dimension of the spirit that is in everything. When the material stuff disintegrates, the spirit remains. I have never seen the ghost of my daughter, but I feel her presence, because I want to, because I write about her, because I have a foundation that does work in her name. Other people feel the presence of God. I feel that everything is imbued with a sense of the spirit, and that has become stronger after Paula died." The spirit of Paula lives easily within the book, much of which is addressed directly to her. Clearly, there is pain in the remembrance of her, but Allende has no desire for the abrupt dismissal of closure.

"I don't want to bury her and forget her. I think of her as I think about my mother; my mother is alive, she's 87 and lives in Chile. I speak to her every day. I'm not seeing her but I am in touch. It's the same with Paula." Instead, she has transformed the ache of memory into something vital and quick. "There is a certain sadness that will always be with me because I don't want to get rid of it, because it's wonderful to have it. It's like a sediment in the bottom of my heart, a very fertile soil. Everything grows there -- creativity, compassion, patience, strength. The best things I have blossom in that fertile soil of memory, of love, of sadness, loss. I don't want to get rid of it."

Side by side with the gentle dreaminess of her spiritual responses is a brisk and forceful practicality. When her family are in trouble, she cooks and knits, getting up at dawn to make huge meals and shapeless jumpers. When she and Willie hit bad times, she drags him to a therapist. And when age begins to call in the favours of youth, she visits a cosmetic surgeon, without the dissembling and evasion such action normally inspires.

"It was a very easy decision. I have a very public life and I saw some pictures of me looking awful and I thought, 'Oh no. Enough of that.' I had a good surgeon, and it was fine." That was six years ago, and at first her son was "absolutely horrified." He hated the idea, and he still says I shouldn't have done it." But then, as we both agree, sons put their mothers in a funny place. Her rationale for the surgery is utterly pragmatic, and rejects the false romanticism of sentimentality. "Yes, I think that every age has its own beauty, but there are things about old age that if one can correct or prevent, why not? For example, warts. Would you like to have a wart with hairs? At no age is that beautiful. Why would you want age spots if there are creams and lasers that can take care of it? There are other things about ageing that you cannot correct, and you have to live with -- you will get shorter, you will lose your hair. As long as you can help, why not? I am very vain. I don't mind wrinkles, but I don't like spots."

This vanity to which she confesses is worn almost as a badge of pride, proof she still belongs with those who are invested with life, the ones who still have something to lose. "My mother is 87 and she is still vain. She still worries about clothes and wants to look good. I'm very vain, I put on make-up every morning, I want my clothes to look good, even in front of Willie. We've been together for 20 years, but I never go around in sweatpants or stuff that I know I look awful in, even if the only witness is him." It is a battle she engages in even when alone. "I get up every day at the same time, have a shower, put on full make-up and get dressed and walk 17 steps to the back of the garden, where I work. And I spend 10 hours alone with the dog. I want to do this for myself, there is a sort of inner discipline to it."

It is a dynamic, focused approach to living, which is, after all, a business. Perhaps unsurprisingly then, her greatest personal fear is dependence. "I fear that with age, I will be dependent. That scares me stiff. It's the emotional dependency I fear -- that you cannot make your own decisions, that somebody else will make them for you, that you are like a child again, and that you might live a very long time like that. It is horrible. I hope I will die before that, or I will kill myself before that. That I will know when to do it."

It's a tough line, but what else would one expect from a woman who learned early from her grandfather that "happiness is pure kitsch, we come into the world to suffer and learn," and who then managed to value the fun and frivolity in life anyway.

- Emily Hourican