British world road cycling champion Lizzie Armitstead believes people will “forever” doubt if she is a clean athlete after missing three drug tests.
The 27-year-old was suspended and faced missing the Olympics before the first test was declared void.
Speaking before Sunday’s road race, a tearful Armitstead told BBC Sport she would “never cheat in life”.
“In this situation I’m never going to win. If I win, people will say it’s because of something else,” she added.
The Yorkshire rider, who won a silver medal at London 2012, is among the favourites to triumph in Rio after winning a Court of Arbitration for Sport (Cas) appeal.
She had her first missed test rescinded after Cas ruled the doping official “didn’t do what was reasonable and necessary” to find her.
Armitstead says she was “in the place where I should have been” and points out she gave a negative test the following day at the UCI Women Road World Cup.
The second strike, relating to an inconsistency on a form over her whereabouts, was a “stupid mistake” which came shortly after she became world champion last year.
She would not discuss the “traumatic” family circumstances which led to missing the third test earlier this year.
Had her appeal not been successful, Armitstead would have faced a ban of up to two years.
“I’m not at the point of accepting it yet – but I will have to come to the point of accepting that people will doubt me forever,” she said.
“I’m absolutely devastated because people are going to judge me and my family. I will never cheat in any walk of life.
“It’s a very difficult time but I’ve kept it together and put it into perspective. I’ve trained very hard and not let it slip.
“It has been very emotional – it has been been a rollercoaster that I’m glad to get off. I’m very grateful to be here to race.”
Armitstead’s former team-mate Nicole Cooke, Olympic road race champion in 2008, had suggested she had little sympathy for anyone who missed three tests – and the pair had a public spat in the lead-up to London 2012 Games.
However, Armitstead believes she will not receive a negative reaction from her current team-mates or Olympic rivals in Rio.
“I think they understand the scrutiny I’m under,” she said. “I feel extremely guilty that I’ve had to put team-mates through extra media questions.”