'His brain was so compromised': Robin Williams' widow describes his 'devastating' final days in new doc

A makeshift memorial to Robin Williams along the Hollywood Walk of Fame, following the star's death in August 2014.

Robin Williams had a thing for small romantic gestures.

The late comedian, who's the subject of the new documentary "Robin's Wish" (available on digital platforms and video on demand), met his third wife, Susan Schneider Williams, at an Apple store in Corte Madera, California, in 2007.

A couple of weeks before he died in 2014, "I had to run an errand at that very same Apple store," Schneider Williams tells USA TODAY. "Out of the blue, he came walking in with flowers and surprised me. I looked at him like, 'Oh, my God, what are you doing?' And he said, 'This is where it all began.'"

That kind and gentle spirit is what most people remember about Williams, beloved for his hilarious and heartwarming turns in movies such as "Aladdin," "Mrs. Doubtfire," "Dead Poets Society" and "Good Will Hunting" (for which he won a supporting actor Oscar in 1998).

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Explained: What is Lewy body dementia, the disease Robin Williams' widow called 'the terrorist' inside his brain?

But that sweetness masked his personal battles, as he had struggled with depression and drug and alcohol addiction since the early '80s, after breaking out on ABC's "Mork & Mindy." His feelings of depression only intensified years later with the onset of diffuse Lewy body dementia, which went undetected until an autopsy after his suicide at age 63.

"Robin's Wish" delves into the science behind LBD, a neurodegenerative disease in which abnormal protein deposits, called Lewy bodies, form in brain cells responsible for thinking, behavior and movement.

The film tracks the difficult final years of Williams' life, as he suffered from debilitating insomnia, paranoia, hallucinations and confusion – all of which were thought to be brought on by Parkinson's, the diagnosis he received less than three months before his death. Similar to Parkinson's and Alzheimer's diseases, LBD robs patients of their cognition and motor skills, but typically progresses more quickly, making basic problem-solving and comprehension difficult for those affected.

"He was the bravest man in the world, playing the hardest role of his life," says Schneider Williams, 56, an artist and brain health advocate who serves as vice chair of the American Brain Foundation. "For someone as brilliant as Robin, who put his heart and soul into his career, to just start losing his abilities ... it was devastating for him to watch what it means to be human slipping through his fingers."

Before Robin Williams' death, it seemed 'he was getting better'

Williams' last screen roles included 2014's "Night at the Museum: Secret of the Tomb" and the CBS sitcom "The Crazy Ones," which aired for one season from 2013-2014. While shooting both projects, the actor would frequently forget lines and fumble words. He experienced extreme anxiety as a result, calling his wife and collaborators at all hours of the day and night, worrying that his performances were subpar or unusable.

"It was getting harder and harder (for him) to get it right, and he was consumed with that," Schneider Williams says.

Insecurities crept into his personal life as well. Growing increasingly self-conscious, Williams often chose to stay home rather than meet up with friends or play impromptu comedy shows. The documentary details how he was prone to panic attacks and thrashing in his sleep, and would lie awake for hours with delusional thoughts.

Several months before his death, Williams awoke with an unshakable fear that his friend, comedian Mort Sahl, was in grave danger. He tried texting and calling Sahl for hours, and desperately wanted to drive over to Sahl's apartment to make sure he was OK. Schneider Williams repeatedly told her husband that Sahl was fine, and they finally went to sleep around 3:30 a.m.

The months to follow proved challenging, but Williams seemed to be on the upswing in his final days, his widow says. The comedian had recently moved into a separate bedroom on doctor's orders, and he was sleeping and feeling better. The night before his suicide, he wished her "Good night, my love," and headed into his room to read on his iPad. They had planned to meditate together the next morning, which had become a daily ritual.

"All signs looked like he was getting better," Schneider Williams says. "We were in the middle of adjusting medications for his Parkinson's and depression, and had just switched a couple of them. It appeared that he was starting to sleep better, and he seemed more engaged and interested in reading. But clearly, that (wasn't the case). Robin's suicide was really a consequence of brain disease; his brain was so compromised. I look at it like, Robin wanted to end the disease – he just didn't realize that meant he would end, too."

A makeshift memorial to Robin Williams along the Hollywood Walk of Fame, following the star's death in August 2014.
A makeshift memorial to Robin Williams along the Hollywood Walk of Fame, following the star's death in August 2014.

Speculation about his suicide was 'devastating' for loved ones

Immediately following Williams' suicide, media reports speculated why he might have taken his own life, blaming depression, financial troubles, and his past struggles with substance abuse.

"That was pretty devastating," Schneider Williams says. "I just blocked it out as best I could because I had to deal with things that were far more important in the moment. And that was getting to the bottom of what Robin and I had just gone through."

Williams' three kids – Zak, 37, with first wife Valerie Velardi; and Zelda, 31, and Cody, 28, with second wife Marsha Garces – do not appear in "Robin's Wish."

Rachel Karten, a spokesperson for Williams' children, confirms to USA TODAY that they declined to participate in the film.

"We had these really intense conversations with some people on their end and eventually they were like, ‘This is all too much new information for us to be a part of,'" director Tylor Norwood says. "I didn't leave with the sense that they were against it."

Schneider Williams hasn't been in touch with any of his children. (They settled a legal battle over his estimated $100 million estate out of court in 2015.)

"We've all moved on and I wish them well," she says. "I'm not aware whether they've seen the film. I hope they get a chance to eventually. I can understand where that might be hard."

For her, it's still too difficult to watch any of Williams' work. But she finds comfort in the strides that have been made in LBD research, and hopes to carry on her late husband's mission of spreading comfort to others.

Two years before his death, "Robin and I were discussing what we wanted our legacy to be in life," Schneider Williams remembers. "Without missing a beat, he said, 'I want to help people be less afraid.' And I said, 'Robin, that's amazing, honey, because you're already doing that. That's your special superpower.' "

If you or someone you know may be struggling with suicidal thoughts, you can call the U.S. National Suicide Prevention Lifeline at 800-273-TALK (8255) any time day or night or chat online.

Crisis Text Line also provides free, 24/7, confidential support via text message to people in crisis when they dial 741741.

This article originally appeared on USA TODAY: 'Robin's Wish': Documentary looks at Robin Williams' painful last days