Writer: 'Britney is highly unstable'

Author Ian Halperin has claimed that Britney Spears is "highly unstable".

Halperin, who is currently promoting his new book Stalking Britney: Britney Under Siege, said the singer is "sensitive" and "insecure".

He told In Touch: "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.

"There's no doubt, based on the last two years, that she is a highly unstable person."

He continued: "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."

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