MASSAPEQUA, N.Y. — For the first time in her life, Marion Johnston says she feels old.

The petite 80-year-old retired school secretary who uses a walker is still adjusting as one of the newest residents at the Bristal Assisted Living retirement community. She moved in November after the howling winds and rising flood waters of Superstorm Sandy destroyed her Long Island waterfront condominium.

Johnston had often thought about moving, but Sandy revealed an uncomfortable truth: “I just can’t be on my own.”

Although New York and New Jersey health care officials say it’s too soon to confirm a spike, some senior care operators say they’ve seen a surge in older people relocating to assisted-living or retirement communities after Sandy. Prolonged power outages, wrecked homes and flooded streets have helped convince even the most stubborn seniors that they may not be capable of living independently.

“Very often you need that little push over the cliff to make you realize,” said Dr. Gisele Wolf-Klein, director of geriatric education at North Shore-Long Island Jewish Health System. She is not surprised to hear facilities are experiencing increased demand. “When your home is leaking and flooding and you’re sitting in the dark, you come to realize you no longer have the skills of survivorship.”

Maryellen McKeon, senior vice president of operations for Ultimate Care New York, LLC, which runs eight Bristal facilities in the New York area, said the company’s 5 percent vacancy vanished after the storm.

“We have the same thing after snowstorms or heat waves,” McKeon said. “Someone may be isolated in a house and realize, ‘My daughter was right,’ and the reality of your vulnerability sinks in.”

Wolf-Klein noted that the move to assisted living can be difficult.

“There’s an acceptance that the independence you cherished for a long time is now coming to an end,” she said. “There’s an acceptance of aging and time marching on.”

Johnston, a widow who raised three children with her late husband, had lived alone in an Amityville condo for the past 14 years. Amid dire storm warnings ahead of Sandy’s arrival, Johnston’s daughter took her mother to her home in nearby Lindenhurst. It was a prudent decision, since the condominium was destroyed by the storm surge, said the daughter, Linda Monaco.

“The canal came up and went through her entire house; water came in the back door and went out the front door,” Monaco said. Johnston has not wanted to return to see the destruction. “I have a china cabinet with Waterford crystal,” Johnston said, only to be corrected by her daughter: “You had a china cabinet; that’s shot.”

Although her own home was spared from flooding, Monaco said much of her community was not as fortunate. Several houses burned to the ground, and a neighborhood was without heat or electricity for two weeks. Monaco quickly realized she could not care for her mother, who was shivering under a mountain of blankets. Within days of Sandy’s departure, Monaco said she was lucky to find a space for her mother at the Bristal facility in Massapequa, about two miles from Johnston’s home.

Johnston still is adjusting to her new surroundings, where residents are monitored by staff and given three meals a day, plus a spectrum of activities from music appreciation seminars and Bingo to trips to Broadway shows.

“I have been an independent person,” Johnston said. “This is the first time in my life that I felt old, and it’s a little shocking. It is a tremendous emotional adjustment.”

Anne Pinter, senior vice president of the national assisted-living company Atria, said her company’s Northeast facilities saw an 18 percent increase in occupancy during October and November, compared with a year ago.

Patty Tucker, a spokeswoman for the Health Care Association of New Jersey — a trade group representing assisted living facilities and nursing homes — said there has been an increase in temporary admissions to assisted living facilities.

But she said it may be too soon to know if those seeking shelter while their homes are repaired will remain permanently. Pinter said her company typically sees about a 30 percent retention rate in those who initially move in temporarily and then opt for permanent residence.

Lorraine Miller lived in her ranch house in the Harbor Isle community of Island Park for 41 years until four feet of water came gushing in during the storm. Miller, who turned 84 on Dec. 24, used to work as a dental assistant for her late husband. He children had been prodding her for years to sell the house and move to assisted living. She finally relented after the storm.

“I really didn’t want to go because I love my home,” she said. But Sandy was the clincher that convinced her to move; she now lives at an Atria facility in Lynbrook. “I can’t go back at this age and start buying furniture and appliances and all the rest. I’m better off here where I get three delicious meals a day and they come and clean up your apartment and make your bed. What could be better?”