Theirs is one of the most memorable love stories in Hollywood history. Inseparable since co-starring in 1958’s The Long, Hot Summer, Joanne Woodward and Paul Newman shared an unshakable bond that endured for 50 years.

He called her “one of the last great broads,” while she said he was “the most considerate, romantic man.” They were made for each other. But now, Joanne, 85, tragically can’t even recall all those beautiful memories with Paul, her one true love, because she is suffering from Alzheimer's disease.

joanne woodword and paul newman

Paul and Joanne embracing in 1963.

“Her health is deteriorating rapidly,” a family insider confides to Closer. “Joanne will occasionally say she used to be married to someone handsome, but that’s it. She doesn’t even remember the love of her life.”

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Shortly after Paul’s death from cancer in 2008 at age 83, Joanne began showing signs of distress. “The girls saw their mom becoming slightly disoriented, but they chalked it up to her depression after Paul’s death,” says the insider. But now the disease has progressed to such an extent that Joanne needs round-the-clock care. “She barely speaks anymore and hardly ever recognizes her own daughters or grandchildren,” says the insider. “It’s heartbreaking to see her this way.”

joanne woodword and paul newman

Paul and Joanne in NYC in 2004.

While they know she doesn’t recognize them, Joanne’s daughters — Nell, 56, Melissa, 53, and Claire, 50 — are steadfast in being there for their mom. “Melissa has been a godsend,” says the insider. She even lives in her parents’ former Connecticut home, next door to Joanne. The health care staff keeps all three daughters apprised of any progress, but it’s grim.

For a period, Joanne was being treated at Yale University’s Adler Geriatric Assessment Center, where a drug trial caused her to gain weight, but she won’t likely return. “She is so far gone that they feel she is reaching her end point,” the insider tells Closer.

To read the full story on Joanne, pick up the new issue of 'Closer Weekly,' on newsstands now!