Some write memoirs for money or attention. Melanie Verwoerd says she has written her autobiography to tell her own story and because of a promise she made to Gerry Ryan to give a true account of their relationship.
But this book was always going to invite a negative reaction and even accusations of unfair profiteering from loyal friends and family of Gerry Ryan.
So why did Verwoerd walk right into that media superstorm by writing it anyway? Is she a glutton for punishment?
One answer surely comes during Gerry Ryan's funeral when, Verwoerd writes: "I felt the deepest despair. I stood at the back. I knew I wasn't part of the ceremony."
Her memoir, When We Dance, is the work of a woman who doesn't want to stand at the back any more.
That's probably why she devotes the first two-thirds of this book to her early life in Africa, hoping, no doubt futilely, that readers don't just skip forward to the bits about Gerry.
The former South African ambassador and Unicef director clearly wants to establish a sense of herself as an intelligent, independent woman in her own right, not merely the consort of a famous man, exploiting his memory on the way to secondary celebrity status.
By the time she meets Ryan, the stage has been set to present the final days she spent with him as a deep and meaningful marriage of minds in its own right too.
In a way, it's a familiar story. Gerry Ryan was with his wife, Morah, for decades and they had five children together.
Any subsequent partner is bound to face a struggle to escape the shadow of the past, and, when death strikes, the first family naturally tends to assert its right of precedence. That has to hurt.
If nothing else, Verwoerd succeeds in showing her time with Gerry as real and loving, documenting in almost trainspotterish detail the hours they spent together, the trips abroad, their joint hopes for the future. "The sharing of ideas became a central part of our relationship . . . we were exactly like a pair of lovesick teenagers," she writes.
At times she becomes almost defiant in her affirmation of their bond.
Autobiography, though, is never neutral. The reader sees only what the subject chooses to show, and if too much is left unsaid then doubts arise. Here the black hole is Ryan's obsession with money. Specifically, the lack of it.
"For weeks he could not eat or sleep properly because of the stress," she writes.
Any true portrait of the man has to disentangle his troubled relationship with money, and where that monthly pay cheque of €30,000 went, but this book pointedly doesn't go there.
Drugs would be one answer, but Ms Verwoerd is adamant that whatever cocaine habit he may have had in the past was all over. She spent hours with him every day; she had access to his phone; she would, she insists, have known.
She makes a convincing case, but again it prompts more questions. What were Gerry Ryan's demons?
Verwoerd admits to still being "aware and cautious of my deep need to protect Gerry", and that's the problem. She constantly seems to be holding back. There may be legal constraints, but, having been ushered in to share so many intimacies, readers cannot be expected to simply turn away discreetly when it suits the author.
How did she feel, for example, when his own accountant warned her not to lend money to Ryan? Why did she do it anyway? By the end of his life, she practically seems to have been supporting him.
She must have had thoughts on the matter, but in her desire to champion Ryan's cause she too often allows herself to become a passive observer rather than an active participant.
Only in the aftermath of his death does the book, paradoxically, come alive.
Verwoerd conveys a powerful sense of a woman who finds herself at the edge of her lover's life at the time of his funeral.
It's moving, but in the end this emotional honesty merely highlights the contrasting reticence of her analysis of the man she loved.
There will always be people questioning her motives in writing a memoir like this so soon after the broadcaster's untimely death, but ultimately the book's greatest shortcoming may be tiptoeing too timidly around the legend.
Perhaps Gerry Ryan asked too much when he said: "You must promise me you will talk about me after my death."
That's a huge burden to lay on anyone -- especially when he already had the chance to set the record straight in his own memoir, and didn't take it -- unless you also give them your blessing to tell it as it was.
Even Ryan's closest friends speak vividly of the prickly, complicated man he was. Verwoerd is too easy on that man, and in the process makes it harder on herself.
Which may be why reading in reverse is the right way to approach When We Dance. The real woman is to be found at the start in Africa. The one at the end has become a secondary character in her own life.