Sarah Ferguson says royal wedding snub was "difficult"

Duchess of York, Sarah Ferguson attends the amfAR New York Gala co-sponsored by M.A.C. Cosmetics to Kick Off Fall 2010 Fashion Week at Cipriani 42nd Street on February 10, 2010 in New York, New York. (Photo by Andrew H. Walker/Getty Images)
Andrew H. Walker/Getty Images
Sarah Ferguson, Duchess of York attends the amfAR New York Gala on Feb. 10, 2010, in New York.

(CBS/AP) CHICAGO - Sarah Ferguson tells Oprah Winfrey it was "difficult" not to be invited to Prince William's wedding to Catherine, Duchess of Cambridge, last month.

The Duchess of York says in an interview scheduled to air Wednesday on "The Oprah Winfrey Show" that she went to Thailand instead. Ferguson says she wanted to be with her daughters, who attended the wedding with their father and Ferguson's ex husband, Prince Andrew.

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Special section: The royal wedding

Ferguson also told Winfrey she believes Prince William's mother, the late Princess Diana, "would be so proud of her son."

The Duchess of York is set to have a show on Winfrey's new cable station, OWN. The six-part docu-series, called "Finding Sarah," will focus on Ferguson getting her life back on track, with help from "Oprah" regulars like Suze Orman and Dr. Phil McGraw.

Last year, Ferguson talked to Winfrey about being caught on video offering access to Prince Andrew for $724,000. She told Winfrey at the time that she had financial problems, had been drinking when the video was made and apologized for her lapse of judgment.

Winfrey is ending her talk show this month after 25 years.