"It's so hard to wrap your head around it, particularly because he was such a manly man," Scott said Monday on "Good Morning America" of when she learned the news.
PHOTOS: Bruce Jenner through the years
Jenner married Scott, the daughter of a Mormon minister and his college sweetheart, in 1972 while he was training for the Olympics. Scott told GMA about the shocking moment when he broke the news during the first year of their marriage.
"He told me he always wanted to be a woman," Scott remembered. "And, understandably, I was speechless. I didn't really know what to say."
Though her first reaction was one of awe and incredulity, Scott said they eventually worked through it.
"It didn't threaten me. It didn't threaten our marriage," Scott explained. Jenner said in the interview that the two broke up years later for other reasons.
Fast forward to Friday night. While the rest of the world learned the news, Jenner was watching the two-hour special with Scott, one of the first people he told.
Scott said it was hard to watch some of Jenner's reactions to the interview.
"Pain. He was tearful at times," she said of his emotions. "It broke my heart."
The interview was good for them in other ways, she said.
"I think it was cathartic to watch it together," she said, adding, "It was pretty intense."
**Editorial Note: During the interview, Jenner referred to himself using male pronouns. ABC News and this station have chosen to follow his lead, though he also referred to himself as "Bruce" and "her."
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