In a new book, the legendary folk singer offers a disarmingly honest look at her wild life, including her bouts with alcoholism, nude photos, her son's suicide, and a rift with Joni Mitchell that never healed.

Five years ago I got a fan email from a woman who claimed to be Judy Collins. She told me she loved my books and invited my wife and me to one of her sold-out performances at the Café Carlyle in New York.

I replied, "Yeah, prove it." (I get a lot of weird emails.)

She gave me her home and cell phone numbers. I called and asked her to sing something.

"Bows and flows of angel hair," she sang in that unmistakable crystalline voice: the opening lyric to "Both Sides Now," Judy Collins's first big hit.

We went to the Carlyle, hung out with her and her husband, Louis, after the show, and since then we've become friends. So I've had the opportunity to observe both sides of the woman, the private and the public. Before one concert outside of Boston, Judy and I had supper backstage with Hadley Taylor Fisk, the sister of her ex-husband, Peter Taylor. Judy brought her own food. When she got up abruptly in the middle of dinner and excused herself, easily an hour before the concert was to begin, Hadley explained, "Oh, it's time for her to become 'Judy Collins.' You'll see."

On stage, she seemed to have been transformed into another person: glamorous, regal, larger than life, intimate yet distant. She told me later that she goes through certain rituals before each performance, besides the usual hair, makeup, and vocal warm-ups: she secludes herself, meditates, and then emerges in a different state of mind. She becomes the public Judy Collins, the folk-singer icon with the amethyst eyes who broke through to a mainstream audience in the 1960s and 1970s with impeccably rendered covers of "Chelsea Morning," "Amazing Grace," the Sondheim ballad "Send in the Clowns," and a lot of other hits.

"I always want to be a sort of bad-ass, and I always come out smelling like a wildflower."

But it's the private Judy Collins that's revealed in her new memoir, Sweet Judy Blue Eyes: My Life in Music. It's alarmingly candid - about her long battle with alcoholism, her son's suicide, her own suicide attempt. This Judy Collins drops acid with Michelle Phillips of the Mamas and the Papas, has love affairs with a string of famous performers (including, briefly, Joan Baez, which convinced her that she preferred men). When we spoke a few days ago she told me she wanted a different subtitle: "Sex, Drugs, Rock 'n' Roll, and the Music That Changed a Generation." But her publisher insisted that wasn't the way people see Judy Collins. "Well, wait till they read this book," she replied. She was overruled. "I always want to be a sort of bad-ass, and I always come out smelling like a wildflower," she told me.

So it's always been. She was born in Seattle and grew up in Denver, where her father, Chuck Collins, had a radio show. (He was also blind and an alcoholic). Trained as a classic pianist, she gave it up in favor of the guitar, moved to Greenwich Village, and began singing folk music. She was discovered by Elektra Records and put out her first album in 1961, A Maid of Constant Sorrow, a collection of traditional folk tunes and social protest songs.

For the cover of her first big album, Wildflowers (1967) she posed nude, but the record label, Elektra, used a chaste-hippie image of her standing in a field of daisies instead. (I asked her where those nude photos were. "I wish I knew! I think they must be in the archives of Elektra somewhere, giving off heat.") A decade later she tried again, posing nude for the photographer Francesco Scavullo. She chose a full-frontal nude for the cover of Hard Times for Lovers, but Elektra went with a far-less-daring, more discreet shot.

Maybe it was the perfect purity of her voice, or maybe her poised elegant beauty, but she couldn't seem to shake that flower-child image. She recalls one night in 1968, at the Troubadour in L.A., when Janis Joplin turned to her (both of them drunk) and said, "One of us is going to make it, and it's not going to be me." Judy doesn't think Joplin was talking about their careers. Two years later Joplin was dead, a heroin overdose mixed with way too much booze. But unlike Joplin's famously self-destructive, Southern Comfort reputation, Judy's alcoholism wasn't apparent. "I was a much more covered-up drunk," she says. "My cover story was different. It was fine for me to say I was an alcoholic. I was rather proud of it, because it meant that I could drink you or anybody else under the table. I was a snob, too. I didn't take a lot of drugs, because I thought they would interfere with my drinking."

"You mean, 'interfere with your singing,'" I said.

"No, my drinking. I also didn't want to go broke. I knew that if I used cocaine, I'd probably go broke. Because I liked it. I was such an addict that I knew I'd get into trouble."

In her new book she talks about the legacy of drinking in her family, which included her father, Chuck Collins, a blind radio host with whom she had a difficult relationship, largely because of his alcohol-fueled rages. And her only child, her son, Clark Taylor, also an alcoholic, who killed himself after a relapse in 1992. Since then, Judy has spoken and written often about suicide. She told me she wishes she'd told him about her own suicide attempt, when she was 14. "You have to talk about it. You have to talk about it to a shrink, but you have to talk about it within your family, too, because that's where the taboo lies. The secret can kill. I believe it."

I asked her how her brothers and sisters - she's the oldest of five siblings - feel about her writing so bluntly about the family they grew up in, which was their family too, after all. I told her it reminded me of Other Desert Cities, the remarkable new Jon Robin Baitz play starring Stacy Keach and asked if she'd seen it. Of course she has. She and Stacy Keach lived together for five years.

They met in 1969 when they were co-starring in Peer Gynt Off-Broadway. She'd just broken up with Stephen Stills. (In the book she describes first meeting Stills at a party in 1967 and being blown away: "He was possibly the most attractive man I had ever seen.") Stills, devastated that Judy had left him for Stacy Keach, wrote "Suite: Judy Blue Eyes" to win her back. I asked her if it worked, even for a while, and she emailed: "No - just made me feel more regret -/."

But after Crosby Stills & Nash debuted it at Woodstock, "Suite: Judy Blue Eyes" became one of the great anthems of the late '60s and early '70s. For Judy, it was like a twist of the knife. "Stephen knew exactly what he was doing," she writes. "He was that smart and that gifted. In a way it was his revenge, served hot, and it was magnificent." In 2007 a set of demo tapes recorded by Stills in 1968 was released under the title "Just Roll Tape," which included another song Stills wrote about her, brief and gut-wrenching, called "Judy." It contains the lyrics: "I'll do anything to please you, will you let me try?"

Judy launched the careers of a number of legendary songwriters, including Leonard Cohen (with her recordings of "Suzanne" and "Bird on a Wire"); she also persuaded him to try singing. And of course Joni Mitchell, who was a songwriter looking for a break when she sang "Both Sides Now" over the phone to Judy. Judy put down the phone and wept, she says. Her recording of Mitchell's song won her a Grammy. She later recorded Joni's "Chelsea Morning" as well, which far outsold Joni Mitchell's own version. Although Joni Mitchell, of course, went on to superstardom of her own, their relationship has always been strained. "She said some things that were rather hostile," Judy told me, "and I probably took them [too] seriously. Perhaps I shouldn't have. I can't call it a friendship, but I certainly admire her without reservation." Joni, for her part, has said that she prefers Dave Van Ronk's creaky, idiosyncratic version of "Both Sides Now" to Judy's. (Seriously?) It was Judy's 1969 cover of "Chelsea Morning" that inspired Bill and Hillary Clinton to name their daughter Chelsea, not Joni's. It was Judy who sang it at Clinton's 1993 inaugural ball, and Judy who slept in the Lincoln Bedroom. ("For eight years," she writes, "I went in and out of the White House like I owned it. I would stay up and talk to Bill until 2:30 in the morning and think, 'My God, when is this man going to let me get to bed?'")

By now I've gone to a number of her recent concerts, and, having listened again to her recordings from the '60s, I've noticed that her voice actually seems to have gotten better in the last four decades, stronger and richer in timbre. This seems against nature, the vocal equivalent of Dorian Gray. I'm not the only one who's noticed this. The New York Times's Stephen Holden rhapsodized last year: "Ms. Collins turned 71 on Saturday, but you would never know it from the unalloyed purity of her soprano. Her slightly unworldly voice is still an instrument that evokes angelic visions in an imaginary cathedral or a shaft of moonlight settling on a lake whose waters are barely quivering." I've seen her voice compared to a mountain stream, an Alpine instrument, an unblemished icicle.

So what's the secret? For one thing, she stopped drinking. She also had laser surgery on her vocal chords in 1977. It was a new and risky procedure at the time, but her surgeon told her that if she didn't have it, she'd never sing again. Then there's her musical discipline. Throughout most her career, even during the period of her greatest celebrity, she continued to take voice lessons. In fact, she now has a greater range than ever: easily three and a half octaves. As the Washington Post's Dennis Drabelle wrote recently, "Too much smoking has reduced Joni Mitchell's voice to a bray. Bob Dylan sounds as if his lungs could use a chimneysweep." Whereas Judy Collins, along among her contemporaries, keeps getting better. She may want to play the bad-ass, but after a half century on stage, she still sounds like an angel.

Bonus Material: What's on Judy Collins's iPod? Of course I have The Pines & Fountains of Rome [by Ottorino Respighi]. The Roches. The Choir of Cologne. A lot of my own songs, because I was working on my new CD, which is called Bohemian. La Mer . . . Crosby, Stills and Nash, Fritz Reiner, Adam Guettel. Adele, of course. Emmy Lou Harris' new album, Hard Bargain, wonderful, wonderful album. Bach. Sting, the Edin Karamazov recording. Edwin Dowling, Sinead O'Connor, Sarah Maclachlan - The Saints, who are on my label. Sadie Jemmett; Robert Plant and Alison Krauss; Rickie Lee Jones; Puressence, I recorded a song with Puressence in the summer, that's a group from Manchester, England. Rachel Sage, Phil Ochs, Paul McCartney, Patti Smith, Play it as it Lays, Pablo Casals of course. Lorendo Almieta - that's the greatest record, if you haven't heard it, Duets for Spanish Guitar. Lady Gaga, the first one. Neil Young. Leonard Cohen, naturally, Laura Nyro... Josh Groban. I love his older things. I'm crazy about "Caruso." I'm determined that I'm going to learn it and sing it. Death Cab for Cutie's on here! I love Death Cab for Cutie. Buffalo Springfield, I want to learn [sings] - "Listen to my bluebird sing." Dolly Parton. Adam Guettel wrote Light in the Piazza - he's kind of a stretch between theater and opera. I was just looking at with my nephew, who's a wonderful singer and performer, Gordon Lightfoot, "The Edmund Fitzgerald." And also a ballad of Stan Rogers, "The Northwest Passage."