'He was drowning in his symptoms': Robin Williams' widow details the actor's final months as rare disease took hold of his brain and robbed him of his sanity

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Robin Williams' widow has revealed intimate moments of the actor's final months of life, recalling in heartbreaking detail how a rare brain disease robbed him of his sanity.

Susan Schneider, the star's third wife, told how he grew increasingly frustrated as the symptoms of Lewy Body Dementia set in, gradually taking hold of his body until his suicide in August 2014.

'It felt like he was drowning in his symptoms, and I was drowning along with him,' she said in a moving article published by the medical journal Neurology. 

Characterizing her husband's illness as a 'terrorist', she revealed that he would become frustrated over forgetting words and was unable to sleep in the months before his death.

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Robin Williams' widow Susan (seen above together in 2013) has told in heartbreaking detail how the couple spent their final months together before his suicide in 2014 

'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,' she wrote. 

Before his death, the pair enjoyed a romantic weekend together which his wife described as 'like one long date'.

With neither of the couple getting enough rest due to the actor's condition, doctors had told them to sleep in separate bedrooms. 

Sharing their final words to each other, Schneider wrote on Friday: 'When we retired for sleep, in our customary way, my husband said to me, “Goodnight, my love,” and waited for my familiar reply: “Goodnight, my love.”

'His words still echo through my heart today.' 

The 63-year-old was found dead the following morning.  

Two months earlier, while filming Night At The Museum 3, he had trouble 'remembering just one line', Schneider continued. 

'This loss of memory and inability to control his anxiety was devastating to him,' Schneider said.

He was also suffering digestive problems, poor sense of smell and had trouble going to the bathroom, she said.  

Williams was diagnosed with Parkinson's Disease on May 28, two months before he took his own life at the coupe's home in Tiburan, Northern California. 

The actor had been suffering the symptoms of Lewy Body Dementia beforehand but it had gone undiagnosed.

The actor visited a rehabilitation center in Minnesota two months before his death, visiting a Dairy Queen while he was in the area (above). It was one of his final public appearances during which he displayed a frailer demeanor than had been seen before

The actor's wife (above during an emotional appearance on Good Morning America after his death) said he could no longer remember some words and was having trouble sleeping in the months before his death

The 63-year-old took his own life before being diagnosed with the rare condition. In one of the last photographs taken before his death, he appeared red-faced and tired  

An autopsy revealed after his death that it had been plaguing his brain function for months. 

Despite the misdiagnosis, the comedian was aware he was losing his mind and was dissatisfied when he was told he had Parkinson's Disease, said his widow. 

'We had an answer. My heart swelled with hope. But somehow I knew Robin was not buying it. 

'Robin was losing his mind and he was aware of it. 

'Can you imagine the pain he felt as he experienced himself disintegrating?' 

Tests carried out after his death revealed he had likely suffered hallucinations, a common symptom of Lewy Body Dementia, but had not revealed them to his doctors or relatives. 

The star had overcome battles with depression and alcohol years earlier. 

In the months before his death, he visited a rehabilitation facility in Minnesota.

At the time a representative said the trip was to 'focus on his continued commitment to sobriety'.

Schneider said this week that her husband's death brought not only the loss of her husband but that of her 'best friend'.

'Not only did I lose my husband to LBD, I lost my best friend. 

'Robin and I had in each other a safe harbor of unconditional love that we had both always longed for. 

Schneider and Williams married in 2011. It was the actor's third marriage 

Schneider said her husband (above together in 2011) had grown increasingly frustrated with his worsening brain function. The actor was diagnosed with Lewy Body Disease posthumously

'When LBD began sending a firestorm of symptoms our way, this foundation of friendship and love was our armor,' she wrote. 

The pair were married for three years before the actor's death on August 11, 2014. 

Susan has since campaigned to raise awareness of brain diseases, specifically Lewy Body Disease which affects roughly 1.4million people across the country every year.

After his death, she claims lawyers acting on behalf of his three children from previous marriages took their wedding gifts from her home when divvying up his estate. 

She was allowed to keep them and the couple's marital home, she later told Good Morning America.