Mandy Moore, one of DJ AM's former girlfriends, expressed her grief over losing a true friend.

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"I am absolutely heartbroken," she said in a statement to Usmagazine.com about her ex, Adam Goldstein, who was found dead in his New York City apartment on Friday at the age of 36. "For those of us lucky enough to have known him, Adam radiated a contagious exuberance for life and also personified the very definition of a true friend."

Moore, who married rocker Ryan Adams in March, only dated the celebrity DJ for two months in 2007. Still, they had remained close, and after he was badly burned in a September plane crash, she flew to his side. They rekindled their relationship for a brief period following the accident.

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"To say that he will be missed beyond words is an understatement," she continued. "My heart goes out to his loved ones."

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Moore, 25, wasn't the only celebrity DJ AM dated. He had a high-profile romance with Nicole Richie -- who is due to give birth to her second child with beau Joel Madden -- for several years beginning in 2004. They were engaged in February 2005 but split a few months later.

Richie has not yet commented on DJ AM's death.

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