Tim McGraw and Faith Hill's divorce is taking a turn for the worst after Hill learned of her country crooner husband's deepest secrets, RadarOnline.com has learned.
McGraw's ex-fiancé Kristine Donahue has been using his last name behind Hill's back — and he's kept in touch with her son from a previous relationship, Tyler Zarbo!
"Tim McGraw was like a father to me when I was growing up," Tyler told The ENQUIRER. "He saw me as the son he never had, and we've stayed in contact. I wish he could have remained as my substitute dad, but it just wasn't meant to be."
Radar previously reported that the couple was planning to adopt a baby boy, but now McGraw, 49, and Hill, 48, are on the outs after the "Breathe" singer also learned that Donahue used the name McGraw on legal documents!
"Tim knew Kristine was sometimes using his last name, and he kept that from Faith," an insider revealed to Radar. "He knew full well that Faith would blow up if she knew — and that ended up being the case."
Sources close to the couple revealed that Hill knew Donahue and McGraw during their engagement, making the betrayal even worse.
"The couples even double-dated a couple of times," the friend explained. "They were all friendly with each other — and Kristine was actually using Tim's last name on legal documents back then."
"She certainly thought Tim was going to marry her, and they'd be together forever," the friend said, noting that "Tim and Faith started sleeping together on the road, and pretty soon both their fiancés were history."
But, McGraw refused to cut Donahue out of his life and even helped her bankroll her housecleaning business. The business went under in 2008, and Donahue filed for bankruptcy under the name "Kristine McGraw" after accumulating nearly $340,000 in debt.
"He always felt badly for Kristine, and how he gave her the short end of the stick," a source revealed to Radar.
McGraw's rep denied to The ENQUIRER that their marriage is in trouble, but friends close to the couple told Radar otherwise.
"Tim and Faith have faced many challenges over the years, but they've managed to keep going," the friend said of McGraw's flirting and partying.
"Still, they just aren't as close as they once were, and learning Tim knew all along his ex was using his last name may be the straw that breaks the camel's back for Faith," the friend revealed.
Do you think McGraw and Hill are headed towards a bitter divorce? Tell us in the comments!
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