The fairy tale image was "one big lie that I repeated a lot of times," Armstrong said. It became impossible to live up to and it fell apart.
He publicly derided those trying to expose him, ruining some of their lives. "We sued so many people," Armstrong told Winfrey -- people who were telling the truth and lost to him in court in spite of it.
It was about controlling the narrative of his heroic story. "If I didn't like what somebody said ... I tried to control that and said that's a lie; they're liars," Armstrong said.
"Now the story is so bad and so toxic, and a lot of it is true," he said.
Be nice to people on your way up.
You may meet them on your way down. Lance has. And now the tables have turned.
"This was a guy who used to be my friend, who decimated me," said Betsy Andreu, the wife of one of Armstrong's former teammates, who went public with doping allegations against Armstrong.
Andreu, author Daniel Coyle, journalist David Walsh, whom Armstrong attacked for writing about his doping for over a decade, former teammates and others he has discredited and sued have now gained plausibility.
They are already critiquing his confession and casting doubt on its completeness. Andreu and Coyle have called Armstrong out over his denial of allegations that he coerced teammates to use performance enhancing drugs.
It's hard to regain trust.
Armstrong's lies and bullying rattled his fans, former friends and teammates, even his own children.
"I will spend the rest of my life ... trying to earn back trust and apologize to people," Armstrong told Winfrey.
Sunday Times journalist Walsh believes the cyclist's bullying was worse than his lies and left behind deeper scars.
"He never showed any compassion during his years or any sense that it troubled him to destroy other people," Walsh said.
Armstrong said he had been ruthless because he "expected to get whatever he wanted and to control every outcome."
"There will be people who hear this and never forgive me," he said. "I understand that."
The emotional damage to his children seemed to touch him the most.
Appearing to hold back tears, Armstrong said he confessed to the three oldest children over the recent holiday break. "The older kids need to not be living with this issue in their lives," the athlete said. "It isn't fair."
Speaking specifically about his 13-year-old son, whom he had heard defending him, Armstrong said he told the youth: "Don't defend me anymore."
Hindsight is 20/20.