Transcript for Robin Williams' Widow Discusses Husband's Tragic Death
an ABC news exclusive. Robin Williams' widow, Susan Williams speaking out for the first time since his death last year and Amy had a chance to sit down with her. After more than a year Susan Williams is breaking her silence opening up in an emotional interview about her husband's suicide and revealing a previously undetected medical condition in his final months. She very much wants people to understand exactly what led to robin's death and what made him the love of her life. It's 060. What does the O stand for, oh, my god it's early. With his quick wit. And a quiet gravitas. You don't know about real loss because that only occurs when you love something more than you love yourself. Reporter: There was no role too great for the brilliance of robin Williams. Old man's love, this is what we stay alive for. Reporter: Yet his most extraordinary role was off screen as a family man. It's the best love I ever dreamed of. You know, it's what I always dreamed of a love would be based on just honor, love, respect. Robin and Susan had a seven heave year relationship, a happy and very private three-year marriage but on August 11th last year, life took a drastic turn. Susan left for work that morning thinking her husband was still asleep. Rebecca, his assistant came over, I said call me when he's up. Then she sent me a text. It said he's not up yet. What should I do? Then I said, wake him and then she called me back. What did she say? I can't -- I can't even -- I'm sorry. That 20-minute car ride I just screamed the whole way, robin. Did you get to see him? Yes, I got to tell him I forgive you with all my heart. You're the bravest man I've ever known. You know, we were living a nightmare. Reporter: That nightmare at its worst in 9 months leading up to his suicide. The 63-year-old was secretly battling depression, anxiety and paranoia which drove him to take his own life hanging himself with a belt. When did you first notice that something wasn't quite right? In November of 2013 he had a little gut pain, next month it was another symptom. It was like this endless parade of symptoms and not all of them would raise their head at once. It was like playing whac-a-mole which symptom is it this month? I thought is my husband a Hy hypochondriac and by now we tried everything. Reporter: Some answers finally came in may that year when robin was diagnosed with early stages of Parkinson's disease. Did he ever do anything where you were afraid for his physical safety? Yes. Yeah, July 24th. I was in the shower and all of a sudden I saw him lingering at the sink for awhile. Something didn't seem right. And I opened up the door and there was blood. The towel was soaked with blood and he was just dabbing his head. I just screamed, robin, what happened? What did you do? Just my best friend was sinking, you know. He pointed to the door and I said, did you hit your head and he nodded. His only response was I miscalculated. Did it ever cross your mind that he could be suicidal? No, it was Chavis going on inside his brain, the chemical warfare that no one knew about. Reporter: His autopsy later revealing he was suffering from a debilitating brain disorder Lou which body dementia. It is a complex disorder with many different presentations. You can see very dramatic effects in thinking, emotions and behavior. Reporter: Most people think your husband killed himself because he was depressed. No, Lewy body dementia killed robin. It's what took his life and that's what I spent the last year trying to get to the bottom of. What took my husband's life. Was he losing his mind? Yes. Absolutely. And he was aware of it. He was keeping it together as best as he could but the last month he could not. It was like the dam broke. In that last week, doctors were planning to check him into a facility for neurocognitive testing. Was this robin's way of taking control back? In my opinion, oh, yeah, I think he was just saying, no. And I don't blame him one bit. Your last conversation with robin, what was said? So I was getting in bed and he came in the room a couple of times once to his closet and he said, good night, my love and I said, good night, my love. And then he came back again, he came out with his iPad and he looked like he had something to do and that was like I think he's getting better then he said good night. Good night. That was the last. Today while the world continues to remember robin Williams for his iconic movies. My favorite movie of robin Williams was robin Williams being a human being, not an actor. Right. Best movie in the world. And Susan told me that robin was completely sober when he died and had been for eight years and she explained that they had been sleeping in separate bedrooms because he had trouble sleeping. That's a symptom, a classic trait of Lewy body dementia. You can see. More of my interview with Susan tomorrow on "Gma" where she talks about the legal battle that then ensued with robin's adult children. All this time many thought it was the depression that led to -- It was dementia. Tomorrow the children. Yes. Thanks, Amy. Coming up, the candidate
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