TORONTO - Anne Murray says she decided to write her tell-all memoir because it was the last item remaining on her career to-do list.

She had no idea how difficult it was going to be.

"All of Me," which hit stores this week, indeed covers everything -- her dizzyingly swift ascent to becoming America's Canadian sweetheart, her lengthy affair with a married man, her divorce from that same man and the series of personal hardships that have marked the past two decades of her life.

And the 64-year-old says she wouldn't go through this painful process of reliving the past again.

"You have no choice but to go through it, but to write about it was awful," Murray told The Canadian Press over the line from her Toronto-area home.

"It was just very painful for me and I had no idea. I had no idea how I would be affected. And so, you know, to be truthful, there was a point where I didn't know whether I could get through the book, because it hurt so much."

She did complete the project -- "I have to do everything 100 per cent, and I have to finish," she said -- and fans have accordingly been afforded an otherwise unseen look at the Canadian songbird's enduring career.

Beginning with her "mostly untroubled" childhood in Springhill, N.S., Murray and writer Michael Posner track the twists and turns of a 45-year music career.

Murray -- she of the squeaky-clean, freshly scrubbed image -- shares plenty of eyebrow-raising anecdotes, including the details of her years-long affair with Bill Langstroth, a television producer who was married with children when he and Murray began an affair while working together on CBC-TV's "Singalong Jubilee."

The relationship began during a trip to Charlottetown, when Murray and Langstroth smoked marijuana together and kissed. Murray wrote that the early years of their affair were difficult.

"However unhappy he might have been in his marriage, he was still married (with two young children), almost fifteen years my senior and also my boss," Murray writes. "But I was falling in love, fast, and powerless to do anything about it."

For years and years, they had to keep their relationship hidden while Langstroth remained married. That Murray had to be secretive about her relationship fuelled speculation about her own sexuality, she says, and might have contributed to the "legion of gay fans" she writes about.

By 1975, after Langstroth had finally divorced his wife, he married Murray.

Writing about the affair, Murray said, was easy. It was ancient history. But delving into her 1998 divorce from Langstroth and a recent onslaught of tragic developments -- her daughter Dawn's struggles with anorexia, the downturn in her career that began in the mid-80s, the guilt she felt over being away from her family for extended periods of time, and the deaths of her mother, her close friend Cynthia McReynolds and her longtime manager Leonard Rambeau, to whom the book is dedicated -- was much more trying.

"It's the divorce and all of that that's uncomfortable," she said. "Going through all of that again ... that was hard to re-live that. It's typical. Everybody's lives are full of good things, some tragic things, and nobody escapes these things."

Of course, there's also plenty of more breezy material covered in the book.

Murray writes of brushes with John Lennon, Frank Sinatra and the Queen, whom Murray accidentally offended following a performance at Canada's 125th birthday party in 1992. In the early '80s, she gave comedian Jerry Seinfeld -- then a little-known comic working the club circuit -- an opening spot on a series of high-profile shows.

She earned praise from a list of luminaries as long as it was diverse, including former U.S. presidents Richard Nixon and George Bush, Sammy Davis Jr., and Wayne Gretzky (and yet Kiss bassist Gene Simmons, when he stumbled into her backstage at the Grammys one year, said: "Oh, my God, it's Ann-Margret.")

She also writes of late British soul singer Dusty Springfield, who made a clumsy, drunken pass at Murray and after being rebuffed, attacked her husband with her fingernails ("Dusty was a lovely person -- when she was sober, she was great," Murray says now).

Murray also engaged in an "extended flirtation" with American actor Burt Reynolds. He sent her flowers, turned up at several of her performances and arranged for Murray to be his musical guest in an episode of "Saturday Night Live."

"Nothing ever came of it," she says now with a laugh. "He just loved the music, he loved my voice."

Murray also writes about her brushes with drugs -- while seemingly everyone around her in music spent the '70s in drug-induced delirium, Murray more or less stayed away from using anything.

"I was never much interested in the drugs," Murray said. "I certainly smoked dope like everybody else the odd time, but you know, I did very little of it. ... I had to have my wits about me. I was the one out on stage, I was the one doing these shows, so I couldn't get involved in that stuff.

"I took my job seriously. I wanted to do it well."

And Murray, judging by her record-setting sales and endless award tally, certainly did.

She was the first Canadian female solo singer to reach No. 1 on the U.S. charts, and also the first to earn a gold record. She's sold 54 million records and has won four Grammy Awards, 24 Juno Awards, three American Music Awards and three CMA Awards.

Yet she says she has permanently closed that chapter of her life. She has retired from music and says she "doesn't particularly want to" sing in public again.

"I haven't sung in a year and a half," she said. "I don't miss it."

But what about her aforementioned list?

"I don't have anything more on the list," she said. "So maybe that's the perfect time to retire, what do you think?"

And yet, Murray says that looking back on her life for "All of Me," tormenting as it was, did ultimately yield a positive result.

"Maybe once and for all, I'll be able to put this stuff to bed, and not have to deal with it again," she said.

"Because boy, some of it is tough."