McGraw, 42, said despite enjoying an active music and film career, he remains happiest when he is with his 42-year-old wife and their daughters, Gracie, 12, Maggie, 11, and Audrey, 7, People magazine reported online Saturday.
"Faith has kept me alive," McGraw told People. "She's saved my life in a lot of different ways -- from myself more than anything. She's loved me through times when I didn't love me."
Without having Hill in his life, McGraw admits he likely would have made some bad decisions.
"I'd be dead. Oh yeah, I would have partied too hard," said McGraw, who is promoting his new album "Southern Voice."
McGraw, who is to appear on the big screen in "The Blind Side," told People he is more stern as a parent than is Hill.
"I'm probably more the disciplinarian. I do try to be tough, not mean, just firm," he said. "You have to be; it's just scary with girls. There's so much that could go wrong."
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