Sally Bedell Smith's new book, Diana, In Search of Herself, focuses on the late Princess Diana's inner life.
Smith came up with new insights, after interviewing 150 people, including friends and relatives, by focusing on Diana's emotional complexity. She shared her analysis with CBS News This Morning.
She concludes that these symptoms are characteristic of a common "but little understood disorder called borderline personality disorder."
Even though Smith is not a psychologist or psychiatrist, she maintains her assessment makes sense.
"When you take all of the symptoms and pull them together and look at the big picture, it seems to indicate, seems to explain behavior that was to many people around Diana inexplicable," she says.
One characteristic of her condition was the ability to present a very sunny public façade and experience extreme mood swings, Smith says.
And because of her position, the late princess was not able to get the kind of help she needed, she points out.
Instead she suggests Diana spent her entire life trying to find out who she was.
"She would spend hours poring over photographs in the daily tabloids, which she read cover to cover. A friend observed she seemed to be trying to define her image in those photographs," she adds.
And the princess' relationship with the press was very confusing, notes Smith. "It was frightening and it was fascinating to her at the same time. She ended up using the press, and the press ended up using her," she says.
The late princess and Dodi's death may soon return to public scrutiny as the state prosecutor in France is reportedly going to release the final report of their death.
Smith's book is already in its fourth reprint with 95,000 hardback copies in print. Author of biographies of William S. Paley and Pamela Churchill Harriman, Smith has also worked at Time magazine, The New York Times and Vanity Fair.
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