Four-time Olympic gymnastics champion Simone Biles believes she should have "quit way before" the Tokyo Games.
American Biles withdrew from five of her six finals in Japan to focus on her mental health.
The 24-year-old, who had been expected to add to the four gold medals she won at Rio 2016, spoke in 2018 about being abused by team doctor Larry Nassar, who is now serving a life sentence in jail.
"If you looked at everything I've gone through for the past seven years, I should have never made another Olympic team," she said in a New York Magazine interview.
"I should have quit way before Tokyo, when Larry Nassar was in the media for two years. It was too much.
"But I was not going to let him take something I've worked for since I was six years old.
"I wasn't going to let him take that joy away from me. So I pushed past that for as long as my mind and my body would let me."
Biles had been seeing a therapist in the run-up to the Olympics and said anxiety set in on her arrival in Tokyo.
In addition to mental health issues, she also experienced "the twisties" – a phenomenon which temporarily affects an athlete's spatial awareness.
Explaining her decision to withdraw from events, she said: "Say up until you're 30 years old, you have your complete eyesight (then) one morning, you wake up, you can't see s**t, but people tell you to go on and do your daily job as if you still have your eyesight.
"You'd be lost, wouldn't you? That's the only thing I can relate it to. I have been doing gymnastics for 18 years. I woke up — lost it. How am I supposed to go on with my day?"
The 19-time world champion returned home from the rearranged Games with bronze in the balance beam, in addition to silver in the team competition.