Together, they watch the evening news and “Colombo” reruns in her living room, said Ms. Schaeffer, 89. “We discuss what’s going on in the world. And he loves animals.” Indeed, Mr. Logan, 63, is studying to become a veterinary assistant and helps feed the feral cat they’ve named Cali, for calico.

“Freda and I are family now,” Mr. Logan said. “We need each other.”

As a graying population confronts the limited options for senior housing, seeking ways to maintain independence without the isolation that can accompany so-called aging in place, various grassroots alternatives are gaining footholds.

Shared housing, cohousing and village organizations appeal to those hoping to avoid the high costs and institutional nature of assisted-living and nursing homes, or at least stave them off for as long as possible.

Though these approaches date back years, “we are seeing a resurgence of people wanting different models of housing,” said Kirby Dunn, executive director of HomeShare Vermont. “Living alone isn’t all it’s cracked up to be.”

A primer: Shared housing matches people who have unused space with people who need housing; typically, at least one party is age 60 or older. Sometimes the arrangement involves simply rent and companionship, but sharers can also agree on lower rent in exchange for grocery shopping, dog walking, driving or other services.