His son has urged him for months to cross the front lines and join him, but Mr. Indershtein, driven by nostalgia and fear, has continued to live alone. He is loath to abandon the home left to him by his wife, who died in 2010. And what would be waiting for him on the other side of the front? “The troops are standing over there,” he mused. “That means the war can’t be far away.”

By the time Mr. Indershtein reached the store, the free bread had run out. He was told to come back the next day.

In Perevalsk, a new patient entered Dr. Polyakov’s office every three or four minutes. The doctor could prescribe some basic medicine like painkillers, but more often patients left empty-handed.

A woman with chronic bronchitis said she had trouble getting out of bed in the morning. Another asked about her husband, who had uncontrollable bouts of coughing. “Did he work in the mines?” a nurse asked. When the patient said yes, she and Dr. Polyakov threw up their hands as if to say, “What do you expect?”

“We will all be that way if we live to a certain age,” Dr. Polyakov said. “Nothing can help, and no one needs you. Most important is that there’s nothing to be had, and it can’t be bought anyway.”