Gene Wilder's widow has praised him as ''the kindest, tender man'' in a heartfelt essay.

Karen Wilder has opened up about her marriage to the late 'Young Frankenstein' star - who died in 2016 aged 83 after battling Alzheimer's disease - and caring for him in the latter stages of his life, to raise awareness about what sufferers and their carers go through.

In an essay for ABC News, she wrote: ''I never pictured myself marrying a movie star. I also never saw myself spending years of my life taking care of one. But I've done both. Love was the reason for the first. Alzheimer's disease, the second.

''The first signs of trouble were small. Always the kindest, most tender man (if a fly landed on him, he waited for the fly to leave), suddenly I saw Gene lashing out at our grandson.

''His perception of objects and their distance from him became so faulty that on a bike ride together, he thought we were going to crash into some trees many feet away from us.

''Once, at a party with friends, when the subject of ''Young Frankenstein'' came up, he couldn't think of the name of the movie and had to act it out instead. (sic)''

Karen feels ''grateful'' the 'Willy Wonka & The Chocolate Factory' actor didn't forget who she was during his Alzheimer's battle, and still holds onto the memory of his last words to her on his deathbed.

She added: ''Gene died fifteen months ago. I was in the bed next to him when he took his last breaths. By that point, it had been days since he'd spoken. But on that last night, he looked me straight in the eye and said, three times over, ''I trust you.''

''I am grateful that Gene never forgot who I was. But many caregivers of Alzheimer's patients are less fortunate.

''Every year, Alzheimer's disease costs our nation an estimated $259 billion, according to the Alzheimer's Association. At this hopeful moment, when there is more momentum than ever towards finding a cure and treatments, let's also remember the desperate need of caregivers. (sic)''

Gene passed away at his home in Stamford, Connecticut from complications from Alzheimer's disease.

During his illustrious career, the Hollywood star - who was diagnosed with non-Hodgkin's lymphoma in 1989 - was also known for his roles in 'The Producers' and 'Blazing Saddles'.