EXCLUSIVE: Scotty McCreery Finally Opens Up About His Longtime Girlfriend -- and the Time He Almost Quit 'Amer

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Scotty McCreery has been tight-lipped about his love life, until now.

"When we first started dating, I was 17 years old -- 18 years old, just kinda been thrust into the limelight, and I said, 'Look, we can call the magazines and have a photo shoot, or we can just kinda keep it on the down low,'" the American Idol alum told ET at the Academy of Country Music Awards earlier this year. "We decided to keep it low-key, but we've been together four and a half years now, so I figure it's time to talk a little bit more about her."

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Scotty, 22, gets candid about his relationship with girlfriend Gabi (whom he met in Kindergarten, by the way) in his new book, Go Big or Go Home, but stops just short of spilling all.

"I let her read the chapter and she was all, 'Oh, you've gotta take that out' or 'Nah, that's good,'" he confessed. "Whatever she asks for, she gets."

Scotty even took a break from his grueling publicity tour to attend Gabi's college graduation over the weekend, taking to Instagram to gush over his girl.

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"I can't wait to see what the future holds for her, but one thing is for certain, she's going to be a great nurse!" he wrote, sweetly adding the hashtag #ThatsMyGirl.

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Scotty also opens up about why he almost quit American Idol while competing in the show's 10th season.

"You get on the show, and your life changes but you as a person don't have to change," the devout singer says, recalling the time he was assigned to sing the song "Everybody's Talkin'" from the X-rated film Midnight Cowboy. Pushing back against industry heavyweights Jimmy Iovine and Nigel Lythgoe, Scotty flat-out refused to play ball.

"I loved the song, but the background behind it made me a little iffy," he explains. "So I told them I didn't want to sing it. They said, 'You don't have a choice.' I slept on it, still didn't want to sing it, so I told them, 'Well, I'm not going to show up on stage this week.' So I kinda forced their hand a little bit."

Scotty wound up singing George Strait's "I Cross My Heart" that week, and eventually went on to win the Idol crown -- but not before scoring a rave review from Queen Bey herself.

"I just love you, boy," he recalls Beyonce saying during a guest appearance on the show, adding an emphatic "woooh" to make him blush.

Today, the 22-year-old is hard at work on his third studio album.

"The album, we're just about there," he says. "Still got a few more songs to cut, so hopefully [it will be out] soon. Real soon."

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