Nicole Kidman's a lifesaver.

Her husband Keith Urban says the actress was instrumental in getting him to rehab in October 2006 — and staying by his side while he kicked his drug and alcohol addiction once and for all. "You kind of credit her for saving your life," Ellen DeGeneres asks Urban, 43, on her self-titled show Thursday. "Is that fair to say?"

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"Yeah, absolutely," Urban says. The country singer's rehab stint — his third in eight years — happened just four months after their wedding. Urban admits that Kidman, 43, wasn't exactly aware of the extent of his substance abuse problems when they tied the knot.

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"I think the truth is that I wasn't aware of just where it was at in my life and how it was just going to come down and take me down like it did," the star explains. "I was probably in such a place of denial that I consciously wasn't aware of it." Regardless, he gushes that the actress "remarkably" supported him through it all. "It's beautiful."

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The couple has a 2-year-old daughter, Sunday Rose — who may have inherited some musical talent. "She sings all the time," Urban said. "We have a piano in the house. We sit around the piano and play!"

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