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At the lowest point of her addiction, the now-37-year-old singer was doing meth daily and almost died, weighing in at just 90 pounds. "It can make you crazy," she tells Oprah.
After almost a year on the drug, Fergie hit rock bottom. "My brain had been playing a lot of tricks on me," she reveals. I thought the FBI was after me. You're kind of living in this alternate reality. It's very strange ... There was a dancing ninja that was on my balcony ... My mind was going some places."
"I started getting really paranoid," she continued. The singer found herself in church one day, hiding out from what she believed was the FBI hunting her down. "I had a conversation with God ... and I said, 'If I go out there and the FBI and the SWAT team's not out there, then it's the drugs and I'm stopping,'" she promised her "higher power."
Fergie started on the road to recovery that very day, with the help of "a lot of therapy, soul searching, discovering why I did the drugs in the first place."
The singer admits her time as a member of the girl group, Wild Orchid, left her feeling conflicted and "inauthentic." "I wasn't being myself," she says. Fearing the prospect of letting her bandmates down by ditching the group to go solo, Fergie turned to hard partying instead. "I didn't know how to deal with that confrontation ... I didn't know how to deal, so I got into a scene." It was at this time the Fergie started taking ecstasy, and eventually, meth.
Watch a clip from her interview with Oprah in the video below.