Donald J. Horsfall, 72, of Rydal, a computer consultant who led a quiet life with his wife, Carol Ann Casciato, in their house with an English garden, died Sunday, March 22, at Abington Hospital-Jefferson Health.

Mr. Horsfall and his wife were the owners of International Technical Communications Inc., a computer consulting business based in their home. She was the vice president, he the president. They coauthored nine books about computing and served a variety of clients.

Other than that, they hung out at their calm retreat in the suburbs and loved each other for 52 years. They were planning to retire next year and move to an apartment in a senior community.

“He played computer games and worked for his company and with me,” his wife said. “We truly were soul mates. We lived together, worked together, liked each other, and spoiled each other. I cooked. Neither of us was a social butterfly. We had a few very close friends.

“He didn’t try to change me, and I didn’t try to change him,” she said.

But their peaceful life was shattered on March 15, when Mr. Horsfall lost his balance while climbing some stairs and fell backward onto a tile floor.

“The next thing I know, boom! It was a stupid accident,” his wife said. “His head hit the floor."

He was hospitalized, but seemed to be doing better by Wednesday, she said. Then he got the coronavirus.

“I really don’t know how — there’s no direct line that we can figure out. There’s no way we can see that he could have contacted anyone who had the virus,” she said.

To keep the virus from spreading, the hospital enforced a quarantine, keeping visitors away. By Saturday, doctors removed the ventilator and tubes, and, knowing that Mr. Horsfall didn’t have long to live, summoned his wife.

“They suited me up and let me sit with him,” his wife said. “I could talk to him and hold his hand for an hour and a half. At least he could see me and know me.”

When the end came the next morning, Mr. Horsfall drifted off to sleep under palliative care. Medical staff said his death was peaceful, but his wife remains saddened that she couldn’t be there.

“It’s hard to tell you how horrible this is. I would have been there, talking to him, holding his hand the whole time,” she said.

The Montgomery County Coroner’s Office said Mr. Horsfall died of the coronavirus. The secondary cause of death was complications from the fall. He was the first patient to die of the virus in Montgomery County. Mr. Horsfall’s wife is now in quarantine at home.

Born in Norristown in 1948, Mr. Horsfall graduated from Eisenhower High School in 1965 and was awarded a scholarship to Drexel University, where he met his wife. Both were science majors, he in chemistry, she in physics.

He decided not to become a chemist because “they don’t live long,” he told her. So, they set up their consulting business. Although a couple for decades, they only married in 2000.

When not working, Mr. Horsfall loved to read science books and science fiction. He was generous to a fault. When the couple’s friends needed help moving into a new house, he was glad to help. He liked to spoil his nieces.

“He was a real good person who didn’t deserve to have this happen to him,” his wife said. “He was gentle and a true gentleman, and will be sorely missed.”

Besides his wife, Mr. Horsfall is survived by a sister and three nieces.

Services are private.

Memorial donations may be made to the Society for Science and the Public via www.societyforscience.org.