Believe it or not, Brad Pitt turned 60 on December 18. A day later, looking as youthful as ever, the A-lister celebrated the milestone with a laid-back, four-hour dinner with his girlfriend of a year-and-a-half, Ines de Ramon, and about 30 friends in a balloon-filled private room at L.A.’s Mother Wolf restaurant. “He was beaming,” a witness exclusively tells In Touch. “He kept Ines close by his side the whole night.”

He’d like to keep her close for a lot longer than that. “Brad is head-over-heels in love with Ines and wants to marry her,” says the source. But after enduring seven hellish years at war with Angelina Jolie over every detail of their lives together — including a $350 million battle over his beloved French vineyard, Château Miraval — “he isn’t taking any chances this time. Brad’s going to insist that Ines sign a rock-solid prenup to protect as much as $650 million in his assets and future earnings.”

He lost a lot because of Angelina. “Negotiations have been excruciating, and the legal fees have been astronomical,” the source says of their ongoing battle, in which she accused him of “looting” the successful winery they bought together, and he accused her of being “vindictive.” He is still reportedly expected to hand over up to $250 million to his ex, 48, for full control of Château Miraval before they finally settle.

Even worse, “he’s put up with character assassinations and has been alienated from his kids,” says the source. Brad no longer has a relationship with Maddox, 22, Pax, 20, and Zahara, 18, while Angie retains primary custody of Shiloh, 17, and Knox and Vivienne, 15. “He couldn’t survive another divorce like that. These have been the worst years of his life.”

His new romance has been the one bright spot. “Ines wasn’t there from the beginning, but she’s seen the toll the divorce has taken on him and has been very supportive,” the source says of the jewelry designer, 34. And while Brad doesn’t “foresee any problems with Ines,” says the source, “his business team wouldn’t let him tie the knot again without taking some precautions.” (Brad’s rep denies that the actor wants a prenup.)

Brad Pitt Wants Wants Prenup to Marry Girlfriend Ines de Ramon: ‘He’s Isn’t Taking Any Chances’
Marc Piasecki/WireImage

Ines has also been through a divorce in the past year, after nearly five years of marriage to actor Paul Wesley. “She totally understands the legal technicalities and that he’d want to play it safe,” says the source. “She doesn’t mind — Brad’s worth it.”

She’s definitely ready to be wife No. 3. “They can start planning the wedding once the prenup is out of the way,” says the source. “They are deliriously happy and in love and can’t wait to spend the rest of their lives together.”

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