The actress, who passed away on Saturday at 79, was Pacino’s “beloved” in the iconic Godfather trilogy, though their real-life romance began in 1974. They finally broke up in 1990 when Keaton gave him an ultimatum to marry, which he didn’t accept.

According to the Daily Mail, the now 85-year-old Pacino wishes he had married her. “I know he will always regret not making his move when he had the chance,” a friend said. For years after their split, Pacino used to say, “If it’s meant to be, it’s never too late for a second chance. Unfortunately, now it is,” the friend added. He admitted Diane was the great love of his life, always calling her “an amazing woman.”

Despite living in nearby Beverly Hills homes, the two never spoke again. A source said, “I once asked him why, and he said ‘There’s no reason to talk. We said what needed to be said back then.’”

In a 2017 interview with the Sunday Times, Keaton said in retrospect it was better that they never married. “I didn’t even want him to propose. I just thought at some point he would marry me. I thought, ‘Don’t even propose, let’s just do it.’ But it never happened, and in the end, it was a blessing for both of us. It would have been a nightmare for him.”

The Oscar-winning actress admitted that although there was love, they weren’t compatible as a couple. “We’re both eccentric. He needed a woman to take care of him, I needed a man to take care of me… It was important to let each other go, to say goodbye. But it wasn’t my choice.”

Keaton revealed she fell madly in love with Pacino during the filming of the first Godfather in 1972. “I was crazy about him. Charming, hilarious, unstoppable in his speech. He had something undefinable, like a lost orphan, a genius but chaotic person. And of course, gorgeous.”

Keaton never married but adopted two children, Dexter (29) and Duke (25). Pacino remains unmarried with four children: Julie Marie, twins Anton and Olivia, and his youngest, Roman.

In a rare public appearance in 2017, Pacino honored Keaton at the 45th American Film Institute Lifetime Achievement Award. “You are an artist, Di,” he said emotionally on stage, adding, “You are a great artist… I love you, forever.”