LOS ANGELES, California (X17online) - X17online already reported on the upcoming Britney Spears expose by Ian Halperin, and now the New York Times bestselling author has revealed more details in a recent interview.

Halperin went undercover as a photographer for 18 months when he wrote and researched Stalking Britney: Britney Under Siege, and he tells In Touch Weekly, “She’s on a high right now, but her life goes in circles. It’s like a roller coaster ride. She’s a person who is highly sensitive, and just one little thing could set her off.”

Halperin writes about how Britney attempted suicide four times after her split from ex-hubby Kevin Federline, and addresses her self-doubt and insecurities, which popped up in her early teen years. He tells the mag, “At 15, she had a huge breakdown and had to return home to Louisiana. She was very insecure and felt like she wasn’t pretty.” The solution? “She went on a huge diet.”

Though Britney has made remarkable progress over the past few months, and she's been photographed looking happier and healthier, Halperin believes she’s far from recovered. “There’s no doubt, based on the last two years, that she is a highly unstable person. She’s on a temporary high right now, but she’s never really dealt with all the problems she had. I don’t think it’s possible to turn over a new leaf just like that.”

Despite his somewhat pessimistic outlook, Halperin does say that Britney is a “good mother, and a good person...In fact, she’s nicer than most of the stars I’ve met. But as Britney once told me herself, her life has always been two steps forward, followed by one step back.”

Halperin has penned similar books about Celine Dion and Kurt Cobain, as well as exposes revealing the dark and dirty secrets of Hollywood, supermodels and other high-profile individuals.

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