BELOVED actress JOANNE WOODWARD is suffering from Alzheimer’s disease and is so out-of-it she thinks her late husband, PAUL NEWMAN, is still alive, say sources.

Joanne, 82, now needs constant supervision and is rapidly deteriorating both physically and mentally,  reveal insiders close to the Newman family. “Those closest to her are trying to keep it quiet, but Joanne seems to be slipping a little more each day,” says a family friend.

“Joanne’s daughters noticed her becoming slightly disoriented after Paul passed away, but now she’s in the full throes of Alzheimer’s. Her recent decline has been heartbreaking and dramatic.”

Most tragic of all, Woodward – an Oscar winner for the 1957 movie, "The Three Faces of Eve" – doesn’t realize her husband is dead, says the source.

“After Paul passed, Joanne said she continued to have conversations with him as a way of coping with her grief,” says the source. “But now she’s mentally declined to the point where she’s completely  forgotten his death. She talks as though he’s in the next room or on location filming a movie.”

The couple, married for 50 years when Newman died, was one of Hollywood’s greatest love stories.

Movie icon Newman – an Academy Award winner for The Color of Money and star of such hit films as "The Sting", "The Verdict", "Cool Hand Luke", "The Hustler" and "Butch Cassidy and the Sundance Kid"  – lost his battle with lung cancer at age 83 in September 2008.

But even before the tragedy, pals feared his usually mentally sharp wife was already showing signs of dementia.

In June 2008, Woodward was reportedly forgetting the names of longtime friends and had to be prompted by staffers whispering in her ear. And she nearly wandered into traffic outside her Fifth Avenue apartment in New York City. An assistant lunged for her arm and pulled her out of harm’s way, but it was “a close call,”  a source divulged.

In the weeks after Newman’s death, she plunged into a deep depression at the family’s Westport, Conn., farmhouse.

Barely able to get out of bed some days, friends worried she had lost the will to live, says a source.

Now, as she battles the cruel mind-robbing disease, the medication she’s taking to slow the progression has caused her to gain more than 60 pounds, according to the source.

“Joanne has become very unsteady on her feet and so confused that the family has hired 24-hour staff to care for her,” the source says.

“She’s had an amazing life, and her children and grandchildren dote on her. They think of her as the family angel, and in a way, there’s a blessing here.

“In her mind, Paul is still with her. He was the love of her life and it’s a great comfort for her

to believe that he could walk into the room at any minute.

“She still loves him with all her heart.”