In the wake of Sandra Day O’Connor’s passing, I saw a photo of her with my father, Ronald Reagan, after he had nominated her to be the first woman on the Supreme Court. They were outside on the grounds of the White House, walking side by side, smiling, obviously in the midst of a conversation. These were two people who were athletic, strong, driven to make a difference in the world.

I find it poignant to see them in that form, knowing, as we now do, that both would later be eroded by dementia. Both would make the rare choice to go public with the news of their diagnosis. And both would die from complications of the disease, which always wins in the end.

But before any of that, the disease would come for Sandra Day O’Connor’s husband, John Jay O’Connor III.

The justice will long be remembered for breaking the gender barrier on the Supreme Court, a brave public victory that reverberated across the American judiciary, across the legal profession she had to fight so hard to join, across the nation’s workplaces. She also deserves credit, however, for having broken a second boundary: She spoke with rare candor about how Alzheimer’s disease plays out — with its heavy responsibility and complex ethical issues — within the private confines of a marriage.

Sandra Day and John O’Connor met in the early 1950s when both were students at Stanford Law School. An appointment to work on a Law Review article together extended into a couple of beers, and soon they’d gone on 40 dates in 40 days. John was charming and impressed by her intellect. By the time he asked her to marry him, she had reportedly turned down three other proposals (including one from William Rehnquist: “To be specific, Sandy, will you marry me this summer?”). She accepted John’s, and they were wed in 1952.

She followed him to Germany when he served in the Army; when they returned, they made their home in Arizona, where they raised three sons until her 1981 appointment required a move to Washington, D.C. “The first 25 years,” she would later say, “he made the decisions — where we would live, what job he would take, what he would do, what our life was going to be. And after I went on the court, I’m afraid I was making many of those decisions … It balanced out.”

When John received his diagnosis, in 1990, Justice O’Connor cared for him as best she could. “In the early days of my husband’s illness,” she later told a Senate committee on aging, “I often took him to court with me because he could not be left alone.” She added, “Many caregivers make similarly difficult decisions each and every day.” As she explained, “Alzheimer’s disease is a family disease.” In 2005, she announced that she would resign to spend more time with her husband. But by the next year, it became clear that he needed a different kind of care. The decision was made to place him in a facility.

My father had died two years before, and during the decade of his illness, I paid close attention to what other people chose to share about Alzheimer’s. There was a notable silence about placing a family member in a facility designed to provide safe, appropriate care. I so admired Sandra Day O’Connor’s openness, and I imagined the thousands of people in similar situations who felt gratitude that someone was shining a light on a dilemma that so many suffer through in the shadows.

In 2007, she went even further, allowing her son Scott to disclose that John had fallen in love with a resident at the facility — and that he did so with the former justice’s blessing. In an interview with KPNX-TV, a Phoenix station, Scott described how his mother would watch John and his new partner sitting on a bench together, clearly smitten with each other. “Mom was thrilled that Dad was relaxed and happy and comfortable living here.” She continued to visit him, though he no longer recognized her.

People with Alzheimer’s lose connections, memories become frayed threads, but the desire for companionship runs deep — deeper than the disease. It’s fairly common for patients to develop new romantic, even sexual, relationships. But it’s something that few people feel comfortable talking about.

A decade later, she spoke again about dementia. This time, it was her own. She did as my father had, writing a letter to “Friends and Fellow Americans.” In it, she said, “While the final chapter of my life with dementia may be trying, nothing has diminished my gratitude and deep appreciation for the countless blessings in my life.” It was her last public statement.

A person’s legacy isn’t all about the grand sweep of history; sometimes it’s about quiet choices that touch the lives of others. We’ll never know how many people were affected by Sandra Day O’Connor’s candor, how many people she inspired to let their own husband or wife find a different kind of happiness than they once would have envisioned. She chose to stand firmly in love and happiness for the man she spent so many years with. That, too, deserves to be remembered.

Patti Davis is the author, most recently, of “Floating in the Deep End: How Caregivers Can See Beyond Alzheimer’s.”

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