Four years ago Anne Nolan spoke out after a childhood of abuse. She explains what happened next

The Nolans, Ireland's most famous singing siblings, have lived through it all – fallouts, marriage break-ups, musical mockery and no fewer than three cancer diagnoses – all in the glare of the media. But in the 33 years since their most successful song, "I'm in the Mood for Dancing", nothing was quite so shocking as the news that Anne, the eldest daughter of the eight siblings, was sexually abused by their father – and that, when she was just 16, he even suggested they run away together and live as man and wife.

It's been four years now since Anne, 61, spilt the beans in her autobiography, Anne's Song. Denise aside, her siblings have not been there for her. She hasn't had much luck with people who knew (and knew of) her father, either. He was one of those men everybody loved and some still come up to her, full of praise for him – either implying or even saying that it can't be possible. Complete strangers, however, have been a different story. The letters of support just keep coming in – and the biggest surprise to Anne has been the number of people who, like her, kept their secret until middle age, often older.

"Some are elderly – that was a real shock at first," Anne says in a soft Irish accent. "I suppose I'd always assumed it was unusual that I'd decided to 'tell' so late in life – that you either did it earlier on or you took it to the grave. But in the past few years, I've learnt that my experience is far from unusual. It's been quite a journey of discovery."

Anne was born to husband-and-wife singing duo Tommy and Maureen Nolan in 1950 and was the second of eight children – six girls and two boys. It quickly transpired that most of them could sing and, like the Osmonds and the Jacksons, they became a family that performed on back-to-back tours, often getting to bed at around 3am, then woken in the morning for school. It was throughout this time that Anne was abused.

Anne told her ex-husband, Brian, when she met him at the height of her singing career in her twenties, but nobody else. Then in 1998, aged 73, Tommy died. "I felt nothing," she says. A few years later, on a big family holiday in Florida, she told her siblings everything. "I have no idea why I chose that moment. Maybe I felt it was safer now that he was dead. Maybe it was just because we were all together discussing him. I just don't know. Anyway, it wasn't planned and they were totally disbelieving," she says. "I wasn't surprised, though. They loved him."

Once they were over the shock, she says, they were more sympathetic. "In the end, there was no question that they believed me." A few years later, when Anne decided to write her book, her youngest sister, Coleen, even found her a publisher.

"I'm very unhappy about the way the book was marketed, though," Anne says. "It was never meant to be a confessional memoir, focusing on this deep, dark secret behind the Nolans. It was supposed to be the story of my life. People had often told me to write it who knew nothing of the abuse. But of course it was a massive part of my story, so it went in and the publishers leapt on it."

On the other hand, writing about the abuse turned out to be surprisingly cathartic. "It made me revisit some very painful memories and enabled me to make sense of them. I'd carried around this awful guilt, for example, that I'd had sexual feelings as a response to the abuse, but I know now that's just the body's reaction. I was also able to come to the realisation that my father must have been ill. Thinking back made me remember a lot of the happy times in our family, too. All this was very therapeutic and the result was the feeling that my life hasn't been destroyed by it, which has been very empowering."

Some of Anne's family were less keen about her telling the world something so private, however, with Bernie among those having publicly disapproved. But anyone who knows anything about the Nolans will know that their rows – as in most families – are complex. Certainly, when four of the sisters – Maureen, Linda, Bernie and Coleen – did a comeback tour in 2008 without Anne, it didn't help family relations. "I was devastated and felt deeply betrayed – they didn't even bother to tell me they were doing it. I don't know what the future holds there, but I do know that I've had to face the last four years without a strong feeling of family support."

Her two daughters – now aged 30 and 24 – are the exception. Anne originally told them 15 years ago when their father, Brian, decided he wanted a divorce. "He cited the fact that I'd let my father babysit the girls as the reason for wanting a divorce, so how could I not tell them?" she says. "Obviously they learnt a lot more when the book came out, but they have been brilliant. I explained that we were indeed lucky that nothing ever happened to them and how sorry and regretful I was and they accepted that. It destroyed their feelings for their granddad, which is sad, but they are very grounded and we are very close."

It is the letters from the public that Anne has been focusing on most recently, largely because they still keep arriving on the doormat. "Many people tell me they've spoken out as a direct result of reading my story. They said they felt that if I could do it, so could they. Others just wanted me to know they'd done it, too – that I wasn't alone. Sometimes it makes me feel I've done something really worthwhile, but so many people, even at this older age, are disbelieved by their families – even cut off from them altogether – and at times, I have felt out of my depth. But the charity the Association for People Abused in Childhood has helped enormously. It has been such a relief to have somewhere professional to refer people to – so much so that I've decided to become a patron myself. My plan is to work closely with them in the future and I hope my story continues to give people 'permission' to speak out themselves, no matter what their age."

Anne's life has taken another unexpected turn. She has just finished her first solo album, to be released in the spring. "I'm a civil servant by day," she laughs. "It's not as if I ever enjoyed being in a recording studio anyway. But then again, that was because it was as boring as hell doing all the 'oohs' and 'ahhhs' in the background over and over again. This time, I'm doing covers of songs I love – from 'Danny Boy' to Barbra Streisand's 'Why Did I Choose You?' – and I'm loving it. I'd go so far as to say it's given me a new lease of life. If it does well, great, but if it doesn't, that's fine too. It will be something to leave the grandkids – and for me, it will have been my light at the end of the tunnel and proof that I have survived."

The National Association for People Abused in Childhood (Napac); 0800 085 3330;