Tragic comic Robin Williams was struggling with crippling mental health issues before he took his own life, it has been revealed.
The genius funnyman was struggling with dealing with his memory loss as depression took a growing grip of him.
"He was sobbing in my arms at the end of every day. It was horrible. Horrible," makeup artist Cheri Minns recalled.
"I said to his people, 'I'm a makeup artist. I don't have the capacity to deal with what's happening to him.' "
His trusted friend suggested he return to stand-up after Williams confided he was struggling with his lines while filming the 'Night at the Museum: Secret of the Tomb,' in Vancouver back in 2014.
"He just cried and said, 'I can't, Cheri. I don't know how anymore. I don't know how to be funny.' "
Williams did not realize at the time that he was suffering from a neurodegenerative disease that was causing him huge mental issues.
The revelations come in the new biography book 'Robin' (Henry Holt & Co.) by Dave Itzkoff, out this month.
The books gives Williams' fans an insight into his tragic final days and the harsh reality of what it's like to lose such a brilliant mind.
Robin McLaurin Williams, born in Chicago on July 21, 1951, had a privileged but lonely childhood, spending hours playing with toy soldiers in his attic. He attended Juilliard, then headed out West to blow up the Los Angeles and San Francisco comedy scenes
Longtime friend Billy Crystal described seeing Robin kill on stage: "It was electric, and we all just sat there and went, 'Oh, my god, what is this?' It was like trying to catch a comet with a baseball glove."
Robin landed the guest role of Mork from Ork on the hit show "Happy Days" in February 1978.
This sparked a spin-off show, 'Mork & Mindy' which, by the following spring in 1979, reached 60 million viewers making him a household name.
Despite battling rampant drug and alcohol addiction he went on to find success on the big screen.
He earned an Academy Award nomination for his portray Vietnam radio host in 1987's 'Good Morning, Vietnam.'
Other critically acclaimed roles came in 1989's 'Dead Poets Society,' 1991's "The Fisher King," and 1997's 'Good Will Hunting,' which landed him an Oscar for his portrayal of a caring therapist to Matt Damon's genius.
Williams boosted his bank balance through hits like Disney's 1992 film 'Aladdin' and played a cross-dressing nanny in 1993's 'Mrs. Doubtfire' and a man trapped in a board game in 1995's 'Jumanji.'
However there were some disasters to like1998's 'Patch Adams" 2002's 'Death to Smoochy'.
His drugs and alcohol addiction continued and he checked himself into a rehab in 2006 meeting third wife Susan Schneider during his recovery, marrying her in 2011.
He married first wife, Valerie Velardi, in 1978, and the two had a son, Zachary, now 35. They divorced in 1988, and the next year, he wed his son's nanny, Marsha Garces.
The two were married for 19 years and had daughter Zelda, 28, and son Cody, 26.
Susan describes him as a 'stimulus junkie'
He would always say, 'You're only as good as your last performance,' wife Susan says in the book.
Failure in shows like The Crazy Ones in 2013 did not help.
"Williams seems exhausted," one review read. "So is this show."
And his brain symptoms started to surface. He began to to complain his indigestion, trouble urinating, insomnia, loss of his sense of smell and heartburn.
A slight tremor cropped up in his left hand, which was attributed to a shoulder injury.
Susan reveals: "It was like playing whack-a-mole. Which symptom is it this month? I thought, is my husband a hypochondriac? We're chasing it and there's no answers, and by now we'd tried everything."
Williams lost weight and his once booming voice became tremulous, and he stooped. Producers and colleagues noticed the change.
CBS canceled the show after one season as ratings dropped from a high of 15.5 million to just about 5 million by the finale.
And sadly he started to exhibit strange behavior. On the set of 'Night at the Museum,' he suffered a severe panic attack and was placed on antipsychotic medication.
Billy Crystal described seeing his old friend after a four-month absence, finding him subdued and frail.
When they said their goodbyes after dinner, Robin burst into tears.
"What's the matter?" Crystal asked.
"Oh, I'm just so happy to see you. It's been too long. You know I love you," Robin said.
On May 28, 2014, Williams was diagnosed with Parkinson's disease, a degenerative disorder that impairs motor functioning.
Doctors assured him that they had drugs that could control the tremors and that he likely would have another "10 good years."
Williams kept his diagnosis close, sharing it only with his children, family members and inner circle.
"I never heard him afraid like that before," Crystal said. "This was the boldest comedian I ever met — the boldest artist I ever met. But this was just a scared man."
Sensing he was running out of time Williams embarked on a 'apology tour' to his children and family, over his behavior while battling addiction.
Williams then checked himself into the Dan Anderson Renewal Center, a rehab facility in Minnesota, so he could manage his illness.
But this wasn't enough — this was not a drug addiction, it was a degenerating brain illness. He didn't know it then, but there was little to be done.
His wife Susan described what he was like, she wrote: "He had a slow, shuffling gait. He hated that he could not find the words he wanted in conversations. He would thrash at night and still had terrible insomnia.
"At times, he would find himself stuck in a frozen stance, unable to move, and frustrated when he came out of it.
"He was beginning to have trouble with visual and spatial abilities in the way of judging distance and depth. His loss of basic reasoning just added to his growing confusion."
Two weeks later, Robin settled down for the night at his San Francisco Bay-area home. It had been a rough day after fixating on his wristwatch collection before retiring to his room.
"As we always did, we said to each other, 'Good night, my love,' " Susan recalled.
When Susan woke the next morning, she noticed the door to Robin's bedroom was still shut. When Rebecca, his assistant, asked how he was doing, Susan optimistically answered, "I think he's getting better."
By 11 a.m., Robin had still not left his room, and his 20-year assistant, Rebecca Erwin Spencer, became concerned. She used a paper clip to open his bedroom door to find him dead aged only 63 on August 11, 2014.
Three months later, the autopsy results came in. The neuropathologist's diagnosis was: "diffuse Lewy body dementia."
Williams suffered from an incurable brain disease that occurs when proteins build up in the brain's nerve cells, impairing its function.
It begins with memory problems and physical stiffness and graduates to extreme personality changes, psychiatric symptoms and eventually death.
Lewy body is the second most common progressive dementia after Alzheimer's disease.
Unlike Alzheimer's, where sufferers have issues forming new memories, people with Lewy body dementia can form new memories but have a hard time retrieving them.
No one can truly understand what Robin faced during those final days, but his best friend Crystal provides some insight into what it must have been like for such a brilliant mind to unravel so violently.
Talking after his death Billy Crystal said: "I put myself in his place. Think of it this way: The speed at which the comedy came is the speed at which the terrors came. I can't imagine living like that."
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