Mel B was "catatonic for days" after being "forced" to watch her own sex tapes.

Mel B

Mel B

The Spice Girls singer had to review the raunchy films her ex-husband Stephen Belafonte had made of them in the bedroom as part of their divorce battle and author Louise Gannon, who co-wrote the 43-year-old star's autobiography 'Brutally Honest' has revealed rewatching the clips took their toll.

Louise told Grazia magazine: "I saw her catatonic for days after being forced to watch tapes Belafonte made of her having sex, I watched her fold her daughter, Madison, in her arms, rocking her to sleep, tears falling on her baby girl's head."

Louise initially found it difficult to get Mel to co-operate with interviews for the book, even though it had been the 'America's Got Talent' judge's idea.

She recalled: "Armed with notebooks, tape recorders and a million questions, I sat down in her home but something had gone wrong.

"Melanie had gone from friendly to hostile. 'I'm not talking about that. Don't ask me that', she said.

"As soon as I stopped asking questions and turned the tape off, she would be fine again. 'Don't forget you're not a therapist', she said. 'Don't ask me about my feelings.' "

And Mel admitted: "I knew, at the beginning, I was being really difficult but I didn't know why.

"I knew I wanted to talk, but I couldn't. That I should trust Louise, but I couldn't.

"That I was boiling with anger and drowning in tidal waves of guilt and shame, even though I kept saying I was fine."

After 10 months of spending weeks at a time with Mel, Louise stunned the star when she revealed she'd been hard at work getting her story down without a need for formal interviews.

She said: "10 months later, Mel said, 'Are you actually ever going to do interviews with me for this book?' 'You have no idea' I said. I had never stopped writing.

"A year later, she got the first draft. Her first response was somewhere between exhilaration, terror and shock. 'F**k. This is me. F**k, f**k, f**k. How did this happen? This is my story. What have you done?' "