“It was a perfect day, we just did what we loved to do together and I know now that he gave me that perfect day, he gave us that perfect day,” she said during the second half of her emotional interview with Good Morning America on Wednesday.
“In hindsight, he knew what he was doing,” she added of that August 2014 day.
The 51-year-old said the Robin she knew was much different than the man he was in public.
“Robin is kind, quiet and sometimes funny at home,” Susan said. “He was meditative, contemplative, intellectual and sometimes very, very funny.”
She added that despite being a “beautiful genius,” his “fears and insecurities were killing him.”
Good Morning, Vietnam! You Have to See This Robin Williams Impression
For much more from Susan Williams, pick up the new issue of PEOPLE, on newsstands Friday.
Susan tells PEOPLE in the latest issue that Robin wasn’t killed by depression, but, instead believes it was one of “50 symptoms” he was suffering from the brain disease Diffuse Lewy Body Dementia or Dementia with Lewy bodies (DLB).
During her GMA interview, Susan also opened up about the lengthy legal battle over her husband’s estate. The dispute between Robin’s children, Zachary, Zelda and Cody, and Susan – who married the actor in 2011 – was settled out of court in October.
While Susan said that her “wounds” and “pain” will never go away, she’s gotten stronger. And she still keeps part of her life with Robin in tact – his slippers remain right where he left them on the bathroom floor, and she said, that is where they’ll stay.