Susan Williams reveals the truth about Robin Williams' death

Nov 3, 2015 at 5:28 p.m. ET
Image: WENN

The widow of late actor Robin Williams says the blame for his death lies squarely with one disease, and it's not the one you think.

Susan Williams told Good Morning America in an exclusive interview that while her famous husband had battled addiction and depression in the past, the paranoia and anxiety he experienced leading up to his suicide were caused by Lewy body dementia, which could not be fully diagnosed until autopsy.

"Lewy body dementia killed Robin," she said. "It's what took his life."

While the family released the information that the disease was discovered after Robin's death, the full extent of its effect on him was unknown until now.

More: 7 Things to know about Lewy body dementia and Robin Williams' death

"People in passing… would say to me, 'God, I wish I had done something more for him. If only I had called him," Susan explained. "And I'm thinking, 'No one could have done anything more for Robin.' I just want everyone to know that. Everyone did the very best they could. This disease is like a sea monster with 50 tentacles of symptoms that show when they want. It's chemical warfare in the brain. And we can't find it until someone dies definitively. There is no cure.

"I've thought about this. Of what was going on in his mind, what made him ultimately commit — you know, to do that act. And I think he was just saying, 'No.' And I don't blame him one bit. I don't blame him one bit."

While Robin had been diagnosed with Parkinson's disease the previous spring, his descent into depression, paranoia and anxiety was caused by this even more sinister disease.

"It was not depression that killed Robin," she told People in another interview. "Depression was one of let's call it 50 symptoms, and it was a small one."

More: Robin Williams' wife opens up about his suicide in chilling interview (VIDEO)

"I've spent this last year trying to find out what killed Robin. To understand what we were fighting, what we were in the trenches fighting, and one of the doctors said, 'Robin was very aware that he was losing his mind, and there was nothing he could do about it,'" she says.

"This was a very unique case, and I pray to God that it will shed some light on Lewy bodies for the millions of people and their loved ones who are suffering with it," adds Susan. "Because we didn't know. He didn't know."

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