Robin Williams’ fans, family struggle to understand his suicide

To fans, Robin Williams was “Mrs. Doubtfire” or “DJ Adrian Cronauer,” but to his children, the Oscar-winning actor was simply “dad.”

Although police have now revealed how Robin Williams committed suicide, the beloved comedian’s fans, friends and even family continue to struggle to understand why someone who spread so much joy throughout the world could find so little in his own life that he decided to stop living.

"I'll never, ever understand how he could be loved so deeply and not find it in his heart to stay," his 25-year-old daughter, Zelda Williams, said in a statement sent to FOX411. "He was always warm, even in his darkest moments."

She added she last saw her father when he recently celebrated his 63rd birthday. It was a day that she and her two brothers spent "sharing gifts and laughter" with their father.

Robin Williams, who made no secret of his decades-long struggles with depression and substance abuse, killed himself by fashioning a noose out of a belt and hanging himself, authorities said Tuesday.

The frenetic funnyman, who got his big break when he starred in the fan-favorite series “Mork and Mindy,” had announced only last month that he was back in rehab to "fine-tune" his sobriety after months of nonstop work. His publicist confirmed after he died that he had been suffering in recent weeks from a serious case of depression.

Still, even family members were caught off-guard when his body was found in his San Francisco Bay Area home Monday morning.

“There are no words strong enough to describe the love and respect I have for my father,” Williams’ youngest son Cody, 22, stated. “The world will never be the same without him.”

Marin County Sheriff's Lt. Keith Boyd said Williams was last seen alive by his third-wife, Susan Schneider, who went to bed around 10 p.m. Sunday. She awoke the next morning and left the couple's San Francisco area home, thinking he was asleep somewhere else in the house.

Around 11:45 a.m., his personal assistant found him dead in a bedroom. A pocketknife was nearby and Williams also had superficial cuts on his wrists.

Boyd said all evidence indicates the actor committed suicide by hanging himself. A final ruling will be announced after toxicology reports and interviews with witnesses are complete.

The lieutenant declined to say if a suicide note was found.

"We still have people we want to speak with so there is some information we're going to withhold," he said.

Like Williams' family members, fellow actors and comedians were devastated by the news.

"I never could have expected this ending to his life and to ours with him," said Chevy Chase. "I cannot believe this. I am overwhelmed with grief."

Word that the actor had killed himself also left neighbors stunned and grief-stricken in the quiet, waterfront neighborhood of Tiburon, where Williams was a popular figure.

"I'm shocked. I loved him. I loved his sense of humor. I loved the spontaneity of his life," neighbor Johanna Dunning said of Williams, who was often seen riding his bicycle through the neighborhood or stopping to joke with kids.

Makeshift memorials of flowers and notes popped up around the country, including on his star on the Hollywood Walk of Fame.

People also gathered to remember Williams at a bench in Boston's Public Garden where he filmed a scene for "Good Will Hunting," the film that won him an Academy Award.

Ben Affleck, a co-star and co-writer on that movie, was among the legions of friends and fans who shared tributes online.

"Robin had a ton of love & did so much for so many. He made Matt & my dreams come true," Affleck said of himself and fellow co-star and co-writer Matt Damon. "What do you owe a guy who does that? Everything."

Williams' family asked that his fans remember him as the kind-hearted man that he was.

"Yesterday, I lost my father and a best friend and the world got a little grayer," his son Zak Williams said in a statement. "I will carry his heart with me every day. I would ask those that loved him to remember him by being as gentle, kind, and generous as he would be. Seek to bring joy to the world as he sought."

The Associated Press contributed to this report.

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