In a new memoir, the world-famous soprano, who once weighed 333 lbs., opens up about her addictions to food, men and alcohol – and explains how she got healthy

When Deborah Voigt was fired for being too fat to fit into a (size 12) little black dress for a production of Strauss’s Ariadne aug Naxos at London’s Royal Opera House in 2004, public outrage was immediate. “It’s incredible someone can get away with saying those words,” Voigt, 54, tells PEOPLE exclusively. “It’s still open season on overweight women.”

Voigt details her lifelong struggles with food in a new memoir, Call Me Debbie (cowritten by former PEOPLE writer Natasha Stoynoff). She writes about her first binge at age 5 (when she slugged back a jar of olives), her late night fast food runs once she got her driver’s license, stuffing herself with Pepperidge Farm coconut layer cakes “until I passed out.”

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“At first I’d say ‘I’ll never go over 180 lbs., then it was 200 lbs.,” she admits. “It just went up and up and up.”

At the same time, she was becoming one of the world’s leading opera stars. In that world it was fine, even expected, to be large. But once she became obese, some directors started to comment. “It was hard being Tosca at 300 lbs.,” she says. “They’re singing about her being so beautiful, and I’m feeling ‘I am not and I will never be.’ ”

While the 2004 firing was humiliating, she now understands the decision. “There’s a difference between being a larger-than-life opera singer and what I was, a poster child for food addiction,” she explains.

Afterwards, Voigt took the money from the canceled performance and scheduled gastric bypass surgery. “I had eaten everything there was to eat,” she says. “How many more binges do you have to have?”

She lost over 100 lbs. But soon, there was another struggle. “My drinking just escalated,” she tells PEOPLE. “It would be nothing for me to go through two bottles of wine, then my blackout would happen sometime around the third bottle.”

Through therapy, she learned about how one addiction can lead to another. Men came next: for a brief time, she even frequented websites for men who wanted “big gals.” “The whole idea of being able to attract a man was so new to me,” notes Voigt. “It was like, ‘Could I?’ Lo and behold, I could, and it was like feeding the monster.”

In 2013, Voigt went to rehab for her drinking. Today, she goes to Alcoholics Anonymous and works on her sobriety “every day.” This spring, she’ll perform in The Merry Widow in Detroit and she’s developing her autobiographical one woman show Voigt Lessons which she’ll perform for the first time in New York on Feb. 26.

“I just let everything out,” says the diva about her new book. “I’m feeling a little naked emotionally at the moment, but I hope it helps people.”

For more on Deborah Voigt, pick up a copy of the latest issue of PEOPLE, on newsstands Friday

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