Frankie Dettori says the competition within Godolphin drove him to the "moment of madness," which resulted in a six-month ban from race riding.
Dettori will not be allowed to ride in any major racing jurisdiction until May 20, after traces of a non-performance enhancing drug were detected by France Galop at Longchamp in September. He will not appeal France Galop's decision, which was announced on Wednesday.
Godolphin recruited this year Silvestre De Sousa and Mickael Barzalona, who won the Dubai World Cup in March on Monterosso, and Dettori increasingly found himself without a mount in some of the biggest races until he announced his split with the international stable in October.
"It got to the stage where I wasn't flavour of the month any more and the love was gone," Dettori, in an interview with England's The Daily Star, said. "I want to be in the No 1 car, not the second driver.
"Inside I wasn't happy, which is why I let my guard down. I made a mistake."
The 41-year-old rider has fled Britain and is now understood to be in Australia with his wife, Catherine, and their five children, having spent some time in Dubai after he was formally suspended from riding last month. Dettori revealed the depth of his embarrassment at his ban, and vowed to make amends when he resumes riding next season.
"I will regret it for the rest of my life," he added. "I have been in hiding since it happened because of the shame.
"People will always remember it. They'll just think: 'He's the guy who got caught with drugs."
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