Robin Williams' Widow: "We Were Living a Nightmare"

In an interview that aired Tuesday on Good Morning America, Robin Williams' widow Susan revealed that doctors had told the comedian he had less than three years to live, and that his paranoia and anxiety in the weeks leading up to his suicide were so bad that he was planning to undergo neurocognitive testing.

"If Robin was lucky, he would've had maybe three years left," Susan Williams told ABC News. "And they would've been hard years. And it's a good chance he would've been locked up. ... We were living a nightmare."

Relive the wacky, wonderful career of Robin Williams

Robin Williams committed suicide in August 2014 at age 63. "I don't blame him one bit," Susan tells ABC News, recalling that on the day of Robin's death, "I got to tell him, 'I forgive you 50 billion percent, with all my heart. You're the bravest man I've ever known."

Though the Oscar winner had always been open about his struggles with addiction, Susan says he was "completely clean and sober," with eight years of sobriety under his belt, when he died.

However, he was suffering from other health problems for the better part of a year, and was diagnosed with Parkinson's disease in May 2014. He also began taking antidepressants around that time. At times, Susan tells ABC News, she felt like her husband was "just disintegrating before my eyes." In the last month of his life, "it was like the dam broke," she said.

Watch clips from Susan Williams' interview here: