In this Daily Mail extract from the book, Diana recalls her stay at Sandringham, the Queen's Norfolk residence, in January 1982, when - four months pregnant with Prince William - she threw herself down the stairs ...
When I was four months pregnant with William I threw myself down stairs, trying to get my husband's attention, for him to listen to me.
I had told Charles I felt so desperate and I was crying my eyes out. He said I was crying wolf. "I'm not going to listen," he said. "You're always doing this to me. I'm going riding now."
So I threw myself down the stairs. The Queen comes out, absolutely horrified, shaking - she was so frightened.
I knew I wasn't going to lose the baby (though I was) quite bruised around the stomach. When he came back, you know, it was just dismissal, total dismissal. He just carried on out of the door.
FAINTING AND THERAPY
I knew what was wrong with me, but nobody else around me understood me. I needed rest and to be looked after inside my house and for people to understand the torment and anguish going on in my head.
It was a desperate cry for help. I'm not spoiled - I just needed to be allowed to adapt to my new position.
I don't know what my husband fed her (the Queen). He definitely told her about my bulimia. And she told everybody that was the reason our marriage had cracked up, because of Diana's eating, and it must be so difficult for Charles.
Prince Philip was also sympathetic to his son. During a ferocious argument with Diana, Charles told her that his father had agreed that if the marriage wasn't working after five years, he could go back to his bachelor habits.
It was at the Expo (visit to Expo '86, a world transport and communication fair in Vancouver) where I passed out. I had never fainted before in my life.
We'd been walking round for four hours, we hadn't had any food and presumably I hadn't eaten for days beforehand. When I say that, I mean food staying down.
I remember walking round, feeling really ghastly. I didn't dare tell anyone I felt ghastly, because I thought they'd think I was whingeing. I put my arm on my husband's shoulder and said: "Darling, I think I'm about to disappear", and slid down the side of him.
Whereupon David Roycroft and Anne Beckwith-Smith, (royal aides) who were with us at the time, took me to a room.
My husband told me off. He said I could have passed out quietly somewhere else, behind a door. It was all very embarrassing. My argument was I didn't know anything about fainting. While Anne and David were bringing me round, Charles went on around the exhibition. He left me to it. I got back to the hotel and blubbed my eyes out.
Basically, I was overtired, exhausted and on my knees because I hadn't got any food inside me. Everyone was saying: "She can't go out tonight, she must have some sleep."
Charles said: "She must go out tonight - otherwise there's going to be a sense of terrific drama and they are going to think there's something really awfully wrong with her."
Inside me, I knew there was something wrong with me, but I was too immature to voice it.
A doctor came and saw me. I told him I was being sick (making myself sick). He didn't know what to say because the issue was too big for him to handle.
He just gave me a pill and shut me up. I just felt miserable.
I shut my friends out because I didn't want to pull them in on it. I would be too embarrassed to ask them to come in for lunch. I couldn't cope with that. I would be apologising the whole way through lunch. My mother tried to give me valium. Someone else tried to take me off it. I never actually took it.
But it was all very strange. There were so many forces pulling me and I didn't have a clue which way to turn.
I didn't get any choice over the people I met for therapy. I didn't take to either of the doctors I was seeing.
One of them drove me mad. He seemed to be the one who needed help, not me. The other would ring me at 6 o'clock, and I'd have to explain to him the conversations I'd had with my husband throughout the day. There weren't many conversations - more tears than anything else.
On the outside, people were saying I gave my husband a hard time, that I was acting like a spoiled child. But I knew I just needed rest and patience and time to adapt to all the roles that were required of me overnight. By then, there was immense jealousy because every single day I was on the front of the newspapers. I read two newspapers, albeit I was always supposed to have read them all.
I did take criticism hard, because I tried so hard to show (the Royal Family) that I wasn't going to let them down. But obviously that didn't come across strongly enough at that point.
We had a few trying-to-cut-wrists, throwing things out of windows, breaking glass (she once threw herself against a glass display cabinet at Kensington Palace). I gave everybody a fright.
I couldn't sleep. I just never slept. I went for three nights without any sleep at all. I had no fuel to sleep on.
I thought my bulimia was secret, but quite a few of the people in the house recognised it was going on, though nobody mentioned it.
They all thought it was quite amusing that I ate so much but never put any weight on. I always kept my breakfast down. I didn't take any vitamin pills or anything. I swam every day, I never went out at night, I didn't burn candles at both ends. I got up very early in the morning, to be on my own, and at night-time went to bed early.
So it wasn't as though I was being a masochist - I was to my system, but not to my energy level. I always had terrific energy.
It went on and on. I just cried at every opportunity, which thrilled people in a way because when you're crying in this system, you are weak and (they think): "We can handle her."
But when you bounce up again, (they think): "What the hell has happened?"
The public side was very different from the private side. The public side, they wanted a fairy princess to come and touch them and everything will turn into gold and all their worries would be forgotten.
Little did they realise that the individual was crucifying herself inside, because she didn't think she was good enough. My husband started to get very jealous and anxious by then, too.
Once, (some years later) William and I were in the swimming pool at Highgrove and I was telling him off, and William turned around to me and said: "You're the most selfish woman I've ever met. All you do is think of yourself."
And I was so stunned. I mean, this is seven years ago (in 1985, when William was three). I said: "Where did you hear that?"
"Oh, I've often heard Papa saying it."
The one thing I've always prided myself on - if I may be so bold - is that I've never been a selfish person. But Charles was always telling me I was being selfish, and I sort of believed it.
(When I danced on stage with Wayne Sleep at the Royal Opera House at an event for the Friends of Covent Garden) Charles was horrified. He said I was too thin.
Inside the system, I was treated very differently, as though I was an oddball - and I felt I was an oddball, and so I thought I wasn't good enough. But now I think it's good to be the oddball - thank God, thank God, thank God!
I had so many dreams as a young girl that I wanted and hoped - this, that and the other, that my husband would look after me. He would be a father figure and he'd support me, encourage me, say: "Well done", or "No, it wasn't good enough".
But I didn't get any of that. I couldn't believe it. I got none of that. It was role reversal. He ignores me everywhere. Ignored everywhere, and have been for a long time.
But if people choose to see that now, they are a bit late in the day. He just dismisses me.
He told a lot of people the reason why the marriage was so wobbly was because I was being sick the whole time. They never questioned what it was doing to me.
I think an awful lot of people tried to help me because they saw something going wrong, but I never leant on anyone.
For a long time none of my family knew about what was going on at all. Jane, my sister, after five years of me being married, came to check on me.
I had a V-neck on and shorts. She said: "Duch (Diana's childhood nickname), what's that marking on your chest?"
I said: "Oh, it's nothing."
She said: "What is it?"
The night before, I'd wanted to talk to Charles about something. He wouldn't listen to me.
So I picked up his penknife off his dressing table and scratched myself heavily down my chest and both thighs. There was a lot of blood - and he hadn't made any reaction whatsoever.
(After I told her) Jane just went for me. She said: "You mustn't let the side down."
And I turned on her and said: "Give me some credit that I haven't troubled any of the family in five years about this."
Their perception is very different now. They're annoyed by the lack of support from my husband.
Jane's wonderfully solid. If you ring up with a drama, she says: "Golly, gosh, Duch, how awful, how sad", and gets angry. But she doesn't do anything about it.
Whereas my sister Sarah swears about it behind my back and says: "Poor Duch, such a s****y thing to happen." But she won't say it to my face. My father says: "Just remember we always love you", and does nothing. And my mother just writes letters when she feels like it.
I suppose Charles has worked out that I'm unhappy. He talked to my sister about it and said: "I'm worried about Di. She's not sleeping, she's being sick - can't you talk to her?"
I was running around with a lemon knife, one with the serrated edges. I was just so desperate.
- Extracted from Diana: Her True Story - In Her Own Words by Andrew Morton
- Daily Mail
Where to get help:
• Lifeline: 0800 543 354 (available 24/7)
• Suicide Crisis Helpline: 0508 828 865 (0508 TAUTOKO) (available 24/7)
• Youth services: (06) 3555 906
• Youthline: 0800 376 633
• Kidsline: 0800 543 754 (available 24/7)
• Whatsup: 0800 942 8787 (1pm to 11pm)
• The Word
• Depression helpline: 0800 111 757 (available 24/7)
• Rainbow Youth: (09) 376 4155
• CASPER Suicide Prevention
If it is an emergency and you feel like you or someone else is at risk, call 111.