The X Factor judge confessed that she couldn't stop crying when footage of her performing oral sex on ex-boyfriend Justin Edwards leaked online.
She discusses the incident in her autobiography Honest: My Story So Far, which is being serialised in The Sun.
"My job as a judge on The X Factor was to smile and be smart and funny. But underneath I was petrified of being made to look like a slapper in front of the nation," she revealed.
Speaking of the moment she found out, she continued: "I went completely numb. The next day it hit me like a train. I couldn't stop crying. It was like my whole world was ending. I had terrible heart palpitations and despair and panic overwhelmed me."
Tulisa also reveals in the book that she was sexually assaulted as a teenager.
Honest: My Story So Far is released on Thursday, September 27.
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