It's only when she loses her sense of humour for good that we'll know the cruel disease has truly taken her from us.
Her husband, Scott, 55, has now detailed her condition which he has revealed was diagnosed in 2014.
The actress, best known for her role as pub landlord Peggy Mitchell in EastEnders, was told about her diagnosis on April 22, 2014, after she underwent a series of mental agility tests, a brain scan and a lumbar puncture. "Thoughts with her husband Scott".
Although she left the show multiple times throughout her 25 years, she made her official exit in 2016.
The news came after it was revealed that the EastEnders' legend has been secretly battling the disease since for four years.
As symptoms appear, you may notice that you or a loved one exhibits changes in mood that could be out of character for them.
However, Scott went to speak to Dominic, revealing: "So I went to see him and, without giving the full situation, confided that she was really struggling to learn lines and wouldn't ever be coming back again after this". I hope she knows how much she is loved.
And boxer Frank Bruno said that he and Dame Barbara "go back many years", and had "many great memories and laughs" with her.
"If you saw the Peggy death scenes, you could see she wasn't reading it".
"I think this needed to be said, it needed to be out in the open", she said.
"He rang me last week and said, "I can't protect her anymore".
Writing on Twitter he said: 'Very proud of Scott and Barbara for speaking openly about Barbara's diagnosis.
'Rather than me living in fear she might get confused or upset, they'll know that if her behaviour seems odd, it's due to Alzheimer's and accept it for what it is, ' he added.
In the article written by Loose Women's Jane Moore Scott told of Barbara's struggle with the disease.
Speaking to The Sun, Mitchell said the following: "Since her 80th birthday last August, a definite continual confusion has set in, so it's becoming a lot more hard for us to hide".
"Many of us know Alzheimer's as a disease that causes memory loss like forgetting names or the day of the week", Aileen Waton, head of dementia for Bupa Care Services explains.
Barbara Windsor bowed out of EastEnders in the summer of 2016, with her iconic character Peggy Mitchell taking her own life.
"Stigma around dementia still exists, and many people are facing it in the shadows".
Mr Parry said there are more than 850,000 people in the United Kingdom living with Alzheimer's and other forms of dementia.