Backstreet Boy Nick Carter exclusively gives In Touch the first look inside his new memoir, Facing the Music and Living to Talk About It. “I could’ve ended up a tragedy,” Nick tells In Touch, opening up about his decade-long battle with drugs and alcohol, which ended in 2008.

“During the height of my problems, I did Ecstasy, cocaine and drank a large bottle of vodka a night,” the '90s pop star laments. Unfortunately, all that partying has left Nick with some permanent damage. “I regret taking Ecstasy,” Nick tells In Touch. “The amount I did caused changes to my brain that are responsible for my bouts of depression now.”

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In his new memoir, Nick, 33, reveals that his unhealthy relationship with Paris Hilton (whom he dated from 2003 to 2004) only fueled his bad habits. “Paris was the worst person in the world for me to hook up with,” he writes. “[She] fed my worst impulses as far as partying.”

Though he’s now living a healthier life, Nick admits every day is a struggle. “It’s hard,” says Nick, who’s engaged to fitness guru Lauren Kitt. “But I’m constantly reminding myself that I like this person better than the person I used to be.”

For all the details make sure to pick up the new issue of In Touch Weekly, on newsstands now.

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