Nancy Reagan was in many ways her husband's opposite -- tough versus easygoing, the worrier versus the eternal optimist.
She was involved behind the scenes influencing her husband on many major decisions, and also went public on some controversial issues against Republican party positions.
"Over those eight years in Washington, in the exaggerated ups and downs of life in the White House, I found what was really important. I found how to serve."
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Reluctant at first to talk of personal matters, Mrs. Reagan went public in 1987 with the fact that she'd had a mastectomy following a diagnosis of breast cancer. At the time, the procedure was seen as a radical step, but the First Lady used her decision to encourage women to have regular mammograms.
In 1985, the Reagan's friend actor Rock Hudson died of AIDs. It put a personal face onto the epidemic for Mrs. Reagan. Even so, it took three more years for her to convince her husband to mention the disease in public.
Their son Ron described the process to PBS.
"If you could personalize an issue, either because of a tragedy like Rock Hudson's, or some other way, that was the way you got to him. And she was well aware of that," he said.
"She would always try and put a human face on something."
By 1994, the Ronald Reagan his wife knew and loved was forever lost to the darkness of Alzheimer's. Mrs. Reagan believed that stem cell research offered promise for the disease and promoted it, breaking with President Bush and conservative Republicans.
"I just don't see how we can turn our backs on this. There are so many diseases can be cured or at least helped," she said.
Nancy Reagan went on to raise millions for Alzheimer's research. It was the last act of a life lived quietly, but with fierce determination.
CBS News' Bill Plante covered the Reagan White House