Ann Romney was guest hosting ABC's "Good Morning America" when she spoke about her depression after receiving the diagnosis 14 years ago.
"I was very, very weak and very much worried about my life, thinking I was going to be in a wheelchair as well," she said. "Turned to horses, my life has been dramatically different. They gave me the energy, the passion to get out of bed when I was so sick that I didn't think I'd ever want to get out of bed."
Mrs. Romney is part-owner of a horse that competed this summer in the Olympic sport of dressage, the equine equivalent of ballet. She spoke about her love of horses while standing in New York's Times Square, petting Paralympic horse Lord Luger as rider Rebecca Hart discussed how equine therapy helped keep her out of a wheelchair.
Mrs. Romney also helped interview the competitors eliminated Tuesday night from "Dancing with the Stars." The beginning of her appearance went a little awry when she said the show's staff turned the heat up too high for her family's Welsh cake recipe.
"I've got a cooking emergency!" she said, smiling as the camera turned to her pulling the cakes off the griddle.
She was filling in for co-host Robin Roberts, who is recovering from a bone marrow transplant. ABC says it is in discussions with first lady Michelle Obama for a similar guest appearance.
In a separate interview broadcast Wednesday on Fox News Channel's "America's Newsroom," Mrs. Romney said she immediately knew as the first presidential debate began last week that her husband would win because of the energy he showed.
"I knew after the first question," she said in the taped interview. "I turned to my son after 50 minutes, and I gave him a nudge, and I said, 'It's 100 to zero right now.'"
Mrs. Romney sharply disputed accusations from Obama's campaign that her husband failed to tell the truth during the debate.
"It's sort of like someone that, you know, in the sandbox that, like, lost the game. And they're just going to kick sand in someone's face and say, 'You liar,'" she said. "I mean, it's like they lost, and so now they just are going to say, 'OK, the game, you know, we didn't like the game.' So it's to me, it's poor sportsmanship."
She said she hopes her husband's performance leads more women to support his campaign because so many of them approach her on the campaign trail to say how they are struggling in the current economy.
"These are real people out there. They're not numbers to Mitt and I anymore," she said. "And I hope that came across, that why Mitt's running, is to make the economic opportunities for people that are out there that are really, really desperate."