While recounting this she prowls over the sisal matting in her black and gold loafers, mussing up her blonde hair and smoking Marlboro Lights with theatrical flounces. We are in Shell Cottage, the three-bedroom house she rents on the grand Carton estate outside Dublin. The room for which it is named, encrusted with thousands of shells from across the world, lies cold and empty across the hall: a neglected showpiece. But the living room is beautiful - walls painted severely white, six gothic windows framing the Capability Brown landscape. The rain is pouring down, but inside it is warm: a log fire burns in the huge fireplace, worn sofas are grouped around it, and a fat ginger cat lolls by the grate.
This is her last day of freedom before starting an eight-month world tour to promote her first album for two years, 20th Century Blues. It consists of edgy covers of Brecht and Weill songs, supplemented by Harry Nilsson's "Don't Forget Me" which she sings with raw poignancy. Professionally, this record is hugely important for her: although Faithfull can and does talk grandly about her fans, the fact is that she recently parted company with Island Records and was picked up for this album (she was lucky here and she knows it) by BMG. Her future in the company depends on its success. "It's been a real mission," she says of the album. "It's not often you get something exactly as you imagine it. When something is in here" - she clutches her head - "or in your heart, that's not enough. It has to be let out so other people can understand it."
She certainly let everything out two years ago in Faithfull, her autobiography. With excruciating honesty she detailed her "discovery" by the Rolling Stones' manager, Andrew Loog Oldham, as a 16-year-old convent girl in 1964, her first marriage at 18 to Cambridge student John Dunbar (and subsequent attempts to bottle-feed their baby in a hypodermic-needle-strewn flat), her four-year affair with Mick Jagger and their split, which triggered a free-fall into full junkiedom culminating in two years on the street in Soho.
She was rescued, when her weight had shrunk to six stone and her front teeth had been punched out, by an old admirer, Oliver Musker, who put her through detox. Later she left him, too, and continued her life as a junkie while marrying her second husband, the musician Ben Brierly, and recording her musical masterpiece, Broken English, in 1979. A later boyfriend jumped to his death from a 36th-floor window and a third marriage, to Giorgio della Terza, a writer whom she met at a Narcotics Anonymous meeting, ended when he ran off with another woman six years ago. Now here she is, drug-free, man-free, and apparently angst-free, too.
But one thing she is not free of, and never will be, is Mick Jagger. For better or for worse, Marianne is Mick's creature: he wrote As Tears Go By, the song which made her a pop star; took her as his lover in preference to the dolly-bird Chrissie Shrimpton ("You're obsolete, my baby / My poor old-fashioned baby"); got her pregnant (she miscarried because she was so anaemic); and took her into his black-edged world of sex, drugs and high fame. When she stopped touring he supported her and her son by John Dunbar and taught her about music, and although it is nearly 30 years since she left him he has never, as it were, left her.
The enduring fascination of Faithfull's story, and what despite her own musical talent makes her more than just a pop star's ex-girlfriend, is her extraordinary decision to leave Jagger. She could have married him and stayed rich and glamorous and successful, but instead she walked out to live on the streets, penniless and forgotten. To be fair, Mick didn't forget her. He tried again and again to see her, even after meeting Bianca Perez Morena de Macias, as she was then. But with the compulsion of a true self-hater Marianne forced him away each time and only succeeded in making him abandon her after deliberately turning up at his house grossly overweight. This was the final masochistic test, of course, and one even Mick was bound to fail. His calls stopped and afterwards Faithfull saw the headlines announcing his marriage to Bianca. ("Mick had finally given in to his narcissism and married himself.") It was a bitter moment. She went into the bar at Paddington station and downed three vodka martinis. Then she set her face against the world and proceeded to annihilate her pain with heroin.
"I loved Mick, that's very important," she says now. "He was good to me and protected me when I was with him. He seriously protected me." But? "But ... I don't know. I think I probably was very frightened. It takes me a long time to fall in love. I can see it very clearly with the Mick thing. The moment I really fell in love with him - and this is obviously psychosis, I haven't got it any more - but the moment I fell very deeply in love with him I felt I had to leave." Why? "I don't know. It's crazy. Now, of course, I know better. That's when you stay. But I didn't know that then. I have to say my mother had something to do with it. I was frightened - very frightened. Frightened of the intensity of it, of my own feelings."
She won't say so, but her decision to leave may also have been bound up with the unequal power balance in their relationship. Her self-destructive use of drugs was a way of tormenting Jagger - for his success, his charisma, for the feelings of insecurity he provoked. One also suspects that although it sounds like a dream, being a rock star's consort must have been more like a nightmare. I put this to her and she looks surprised. "People are beginning to see through those myths, aren't they? Like the fairytale wedding. For years people were fed all this stuff and they believed it. People are becoming a lot more sophisticated."
In her book she wrote about the Jagger period. At first they were flying with happiness, but it wasn't long before she was too out of it on mandrax to be able to communicate properly. Then came the scenes at the Courtfield Road flat owned by Brian Jones and his then girlfriend, Anita Pallenberg, where they would all drop acid and Faithfull would sleep with Brian, or whoever asked. She was there when Jones's ex-girlfriend turned up with their two-year-old son and, in a truly Dickensian scene, held it pitifully up to his window asking for money. The gang was all out on the balcony to watch this, and found it hilarious. Another time Pallenberg was alone on the balcony tripping when Richards crept up beside her. "Jump, why don't you," he whispered. At one point Faithfull was in bed with Jagger when he began fantasising loudly about what he would like to do with Keith, who was awake in the next room. It was that kind of scene, and it helped drive Brian Jones mad.
Faithfull suggests in her book that one of the reasons she left Jagger (and this may be the nub of it) was that she might not have lasted the pace anyhow: at the end of the Sixties she overheard Ahmet Ertegun, then head of Atlantic Records, advising Jagger to drop her. ("We simply can't afford someone that out of control. She could jeopardise everything." "Yeah, yeah, I know, man.") It was after hearing that little exchange that she walked out.
Intriguingly, she now doesn't believe that Jagger wanted to get rid of her. "He was changing, and I didn't know - I didn't trust him, I'm afraid to say. I didn't think I would be able to live up to the sort of thing he appeared to want." (Jagger was increasingly courting British aristocrats, a circle in which Faithfull was vehemently uninterested.) She also mentions in her book that living with someone so successful generated a competitiveness in her which could never be satisfied. How do you compete with one of the world's biggest stars? But she doesn't admit to that any more, either. "The envy wasn't in me. No! No! In other people. They hate you. But it was a big mistake to leave. In that situation, do nothing. Being kicked out isn't the end of the world anyway. Just an ego blow."
She has also changed her mind about the Jagger-Ertegun conversation she overheard and when she talks about it, rewriting history, I actually start to wonder if she wants to get back together with Jagger; she has been so wholly admiring of him throughout our talk, and has clearly never met anyone else who matches up. "Well, when I think about it Mick didn't say that," she says. "He was there, but he didn't leap up at that moment shouting: 'Get out of my house, how dare you!' He must have been having doubts himself. I don't know, how do I know? I always think things probably happen in the end, however hard they are, for the best. But I can't spend my life regretting these things. It's too much."
She still keeps in touch with the Stones - sort of. Jones didn't last long, of course. But she saw Jagger when he was in Ireland earlier this summer. Richards is not so friendly. "Keith and Patti [his wife] were just here in Ireland, staying down the road, but I just had this tiny little operation so I'm particularly tired at the moment and I need to take tremendous care of myself," Faithfull explains. "I knew Keith was here and I would have loved to see him, and I know he would have loved to see me. But he didn't call me, and he was absolutely right, because I have to take care of myself and I have work to do." It must be said, however, that Faithfull barely features in Richards' autobiography. She is mentioned four times, most notably in passing as Jagger's "regulaire at the time".
Has Jagger read her book? Yes, she says, and only then would he have known that she still loved him when she left. "He never knew! He would never have realised from my behaviour. But he's older and wiser now. He's figured it out. He's read the book for all that nonsense then he read it again and underneath you see the subtext." So have they discussed it? "Oh no! That's taboo! He doesn't like it. But I wrote it with someone [David Dalton, her ghostwriter] who didn't like him. You have to remember the American publishers have their own agenda. I found it very depressing. They kept saying to David: 'Go and put more about heroin in, more about the pain.' I think they would have liked it best if I'd become a hooker - that would have been a great dirty secret! I was much too hopeless for all that. Let alone having the guts to sell my body. I'd never be able to do that. I'm free. I come free!"
I cannot resist, so I ask her: what did it feel like on the streets - she draws this dreadful picture of herself in the book, getting thinner and thinner in her exquisite clothes from her glory days. "I didn't feel any emotion. It was a long time ago," she says flatly. But she must have done, I insist. "Well, as little as possible," she replies. Suddenly she loses her temper: "Listen, you don't have to know about this because I did it for you and I can tell you it's not fun!" But I don't understand why you were so determined to destroy yourself, I say. "Well, I don't understand it either! But what I found was that I did not want to destroy myself. It was a big mistake and I was lucky in that I was allowed another chance."
So she and Richards have written their life stories, but not Jagger. Is it because he can't remember what happened? "Of course he could! He has tried. But it's too painful. I tried to remember every painful, humiliating moment because it was the only way to do it. It's so honest so people know I'm not lying. The whole thing with the Mars Bar hurt me terribly. It's not true and I'll never find it funny. It's not even just the Mars Bar. The worst thing is that David [Dalton] thought I gave Jimi Hendrix his last fix."
Faithfull has finally got where she wants to be, musically at least, with this new record. "Broken English was wonderful but I wasn't ready, I wasn't there yet. I was expecting to make that record then die. That's why it's like that - all that fury, all that intensity, all those years of pain went into Broken English. That's why I can't make another one like it. I don't want to go back into that place. But 20th Century Blues is like Broken English," she continues in a characteristic self-contradiction. "It's about courage. About not giving in. It's about 'Mon Ami, My Friend' [one of the Brecht / Weill songs on it]. That's the epitome of it." She leans forward and heavily emphasises the words. " 'My friend she does not sit and grieve / But sings away her sorrows to cheer the solders' needs / For life is short and funny / And love must have an end / An hour may be forever / Oh mon ami, my friend.' That's it. That's the point. And it's wonderful - let's have lunch."
! '20th Century Blues' (RCA, CD/tape) is out tomorrow. Faithfull is performing at the Almeida, N1 (0171 359 4404), tonight to Tues.Reuse content