His was a love story, Charles Snelling wrote, a tale of a dreamer and the woman who saved him, of the life they built and the disease that stood no chance of erasing it. By the end, he said, their time together had become a case study in reciprocity.

"She took care of me in every possible way she could for 55 years," Snelling wrote of his wife, Adrienne, months before the two celebrated their 61st wedding anniversary. "The last six years have been my turn, and certainly I have had the best of the bargain."

On Thursday, months after contributing a poignant online essay to The New York Times about dealing with his spouse's Alzheimer's disease, Snelling killed his wife and himself, the Snelling family said in a statement released to The Morning Call of Allentown, Pa.

In the statement, the Snelling family said Charles Snelling had acted "out of deep devotion and profound love."

The Snellings were found Thursday in their home in Lehigh County in eastern Pennsylvania, police said. Charles Snelling shot himself, the coroner said. The ruling on Adrienne Snelling's death was pending. Both were 81.

She was an accomplished fine-arts photographer; he was prominent in Republican circles and had recently stepped down as chairman of the authority overseeing Reagan and Dulles airports in metropolitan Washington, D.C.

Three years ago, Adrienne Snelling wrote letters to her children and grandchildren explaining how she and her husband had decided to cope with her Alzheimer's. "As you know I have Alzheimer's. It is not a nice disease. So far I have held up pretty well. Dad and I are still having a pretty good life. There is no doubt where my sickness will end up for me," she wrote on Nov. 22, 2009.

She went on: "All of our lives, Dad and I have talked over our end of life beliefs. We are both in agreement that neither one of us wants to live after all reasonable hope for a good life is over."

One of the couple's children, Marjorie Snelling, 56, of Philadelphia, said Friday that she knew her parents had talked about a plan to end their lives, but that she and her siblings were stunned that it happened. There had not been "any specific signs."

Still, she said, her family believes the pair "were deliberate and thoughtful."

Charles Snelling, who had a pacemaker and had undergone two knee replacements, was his wife's main caregiver, although he had hired helpers who came in about 14 hours each day, his family and friends said. "They were always deeply committed to each other," Marjorie said of her parents. "They had a fundamental bond."

The romance began when they met at a prom at Cedar Crest College in Allentown. Both were with other people at the time, but in the December 2011 essay in The New York Times, Charles Snelling described his wife as a "simply marvelous young lady: ravishingly beautiful, bright, well-groomed, well-spoken, mannerly, disciplined and circumspect." He "pursued her with all the vigor at my command."

They married on March 21, 1951, the first day of their spring break, and went off for a quick honeymoon in Bermuda.

The two had five children — one every two years over the early years of their marriage — and 11 grandchildren.

Charles Snelling was born into a successful family, the son of Walter Snelling, an aristocrat and scientist who invented ways to better use gasoline; he sold a patent to John D. Rockefeller for $200,000 in 1910.

A 1954 Lehigh University graduate, Charles Snelling went on to have a vibrant career. He worked as an engineer and inventor and dabbled in real estate, running an orchard and a chain of restaurants. He was a pilot, held 20 patents and founded Cryo-Therm, a company in the thermodynamic-energy-storage business.

Over the years, he served as four-time president of the Allentown City Council and finance chairman of the Republican Party in Pennsylvania. He was appointed to the Metropolitan Washington Airports Authority (MWAA) board in 2003 by President George W. Bush and was chairman from January 2010 to December 2011.

Even as he was overseeing the board, his wife was never far away. He often would bring her and her caregivers with him when he traveled to the Washington area or elsewhere.

"You could tell above everything else they were the best of friends," said Mame Reiley, a longtime friend of the Snellings.

Reiley described Adrienne Snelling as a "dynamo" before becoming ill. "She always kept his ego in place," she said.

In the essay, Charles Snelling wrote that although he had "wonderful helpers" caring for his wife, "real care for a loved one with Alzheimer's cannot be delegated. I did not need to be told that; I felt it in my bones."

"The Life Report: Charles Darwin Snelling. A Love Story and Redemption" was the title of the essay.

"It never occurred to me for a moment that it would not be my duty and my pleasure to take care of my sweetie," he wrote.

One recent Christmas, Charles and Adrienne Snelling sent cards that showed them walking hand in hand with their backs to the camera.

It said, "going home."