Bristol Palin Bristol Palin

Bristol Palin admits she lost her virginity while drunk on a camping trip in her new memoir "Not Afraid of Life: My Journey So Far."

Palin writes that she got drunk for the first time on wine coolers and then lost her virginity to boyfriend Levi Johnston, according to the Associated Press. She awoke the next morning with Johnston talking "with friends on the other side of the canvas."

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After that night, Palin vowed to her mother, Alaska governor Sarah Palin, that she'd abstain from sex until marriage. She continued to have sex and at 18 became pregnant.

Palin's book, co-written by Nancy French, covers her family and her mom's run for vice president, but focuses on Johnston, whom she calls a "gnat ... constantly spreading false accusations" against her family. The two were engaged but called it off two weeks after the birth of their son Tripp and then reconnected in 2010 and again became engaged. They called it off three weeks later.

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"I'd just made a complete fool of myself and given my family the middle finger," she says after learning Johnston was cheating on her. His side of the story will be told in his upcoming book, "Deer in the Headlights: My Life in Sarah Palin's Crosshairs," due for publication this fall.

Palin adds in her memoir, out next week, that she's "just a normal girl who couldn't hide her problems and learned a few lessons along the way."

Will you buy her book?