Though Mel Gibson expressed his sorrow this week over the death of Heath Ledger, he had actually distanced himself from the younger Australian actor in the years since Ledger played a gay cowboy in "Brokeback Mountain," according to the New York Daily News.

Ledger chose not to follow Gibson's advice against taking the "Brokeback" leading role of Ennis Del Mar, a ranch hand who falls in love with another male cowboy and all the while struggles with his homosexuality, private investigator Paul Barresi told the News.

As a result, Gibson pulled back from the friendship with Ledger, whom he'd gotten to know when Ledger played his son in "The Patriot."

Barresi said a "major Hollywood producer" told him that Ledger asked Gibson whether he should play the part of Ennis, and "Gibson strongly counseled against it. The role apparently ran counter to Gibson's morality. And he felt that it would ruin Heath's career," the News reported.

But Ledger ignored the suggestion and signed on to do the film anyway, leading to a rift with Gibson, according to the News.

"When Gibson parted ways with Heath, it broke his heart," Barresi told the paper.

In the end, Ledger's performance in "Brokeback" won him critical accolades, an Oscar nomination and newfound respect as a serious, talented and complex actor, allowing him to shed his image as just another Hollywood heartthrob.

In 2006, Ledger told London's Evening Standard that his decision to play Ennis "was kind of a reaction against the comparison that I'm the new Mel Gibson."

On Tuesday, Gibson issued a statement calling Ledger's death "a tragic loss."

“I had such great hope for him. He was just taking off and to lose his life at such a young age is a tragic loss," he said. "My thoughts and prayers are with him and his family.”

Click here to read more on this story from the New York Daily News.