"It's All About Him: Finding the Love of My Life," an account that includes details about the Jackson's marital strife -- including a brief separation at one point and a subsequent spiritual reawakening -- recently topped the New York Times Bestsellers list. The "Him" in the title, she said, refers to God and not her husband.
"I just never dreamed it would be this" successful," Jackson said. "I knew people would want the book because of Alan, obviously but I never dreamed it would be like this. I'm finding it hard to believe."
Alan Jackson wrote a foreword for the book and recorded a two-song CD that includes "That's the Way," which he sung for his wife at their wedding in 1979.
The Jacksons have three children, aged 17, 13 and 9.
'Happy' fan videos make Pharrell cry [VIDEO]
Pistorius testifies he didn't consciously pull trigger when he shot girlfriend