“It was rock bottom. I had completely and utterly destroyed myself," Fergie explained on the US series Modern Hero.
"I murdered myself. I must have brought that on for myself mustn’t have I?
"Because that’s how I felt about myself. Self-hatred at its height.
“I think it just played into my abandonment.
"We both agreed that we didn’t fight hard enough to keep it together.”
Fergie also discussed her daughters, Princess Beatrice, 30, and Princess Eugenie, 28.
The former royal revealed she has been “the mother she always wanted”.
The Duchess said: “Beatrice calls me the most misunderstood woman in the world. She is just the finest example of understanding and learning about how to deal with life challenges.
“Eugenie, she dares to be different.
"She dares to dream, dares to explore new ideas and new ventures.”