Ben Affleck Owes "Everything" to Robin Williams

"Robin had a ton of love in him," the Good Will Hunting actor says

Ben Affleck has broken his silence regarding Robin Williams' death.

The "heartbroken" actor posted a heartfelt message via his Facebook page Tuesday, less than 24 hours after his 63-year-old Good Will Hunting co-star died of an apparent suicide. "Thanks chief - for your friendship and for what you gave the world. Robin had a ton of love in him. He personally did so much for so many people," the 41-year-old actor wrote. "He made [Matt Damon] and my dreams come true."

"What do you owe a guy who does that?" Affleck asked. "Everything."

Affleck concluded his message by writing, "May you find peace my friend. #RobinWilliams."

In 1998, childhood pals Affleck and Damon won the Academy Award for Best Original Screenplay for Good Will Hunting. Williams, who played Dr. Sean Maguire, took home the Best Supporting Actor Oscar.

Had it not been for Williams, the movie might never have been made. "I sent [Harvey Weinstein] a fax that literally said, 'Dear Harvey, I am the Rainmaker.' He called me and he was like, 'What does that mean?' He thought I was getting a lawyer or something," Damon, 43, told Boston in January 2013.

"I was like, 'No man, I got the Coppola movie. They cast me as the lead,'" Damon continued. "And Harvey goes, 'THE GRISHAM MOVIE? THOSE THINGS MAKE $100 MILLION!'" Affleck couldn't believe his co-star "would tell that story about himself." He confirmed that it happened, but Weinstein didn't green-light the movie. "I think he was buoyed by it," Affleck said, "but Robin really was the rainmaker."

"Robin had just done Jack with Francis Ford Coppola. When he read the script and really liked it, his one question for Coppola was, 'Who are these guys?'" Damon recalled.

In fact, according to Williams, "That used to be the joke: 'I want to see some ID.' I read it and went, 'This is really extraordinary.' The Sean character had such history that I was going, 'Where did it come from?' I found out later that it's based on Matt's mother and Ben's father, kind of a synthesis of the two."

Sixteen years later, Affleck was just as proud. "When I look at my own career, my life, and particularly directing, it's all rooted in this experience," he said. "Realizing that the actors need to take responsibility for their performances, and that there is no right answer and that it's just about discovering things."

Williams was, too. "It's more than a movie for some people," he said, "which is kind of wonderful."

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If you or someone you know needs help, please call the National Suicide Prevention Lifeline at 1-800-273-TALK (8255).