It is difficult to come to grips with everything that has happened in the past three years. How it all started: On Christmas Eve 2005, A. and I watched as my mother nearly fell down the stairs of our 1916 four-square house. I still remember it vividly. My mother looked ghostly, stricken. She’d been upstairs in the bathroom for a time, she said, struggling to get her breath. Now she clutched my arm: “I can’t breathe.”

A flurry of activity: Shepherding her to an antique Windsor chair in the kitchen, away from the hubbub of the living room where Paul Desmond’s jazzy sax played on the stereo and birch logs snapped in the fireplace and family and friends chattered over the detritus of recently opened presents.

I rushed upstairs to ferret out an inhaler a doctor had given me for the odd wintertime wheeze. On the way back I detoured to the living-room chair where my red-vested father sat, joylessly, detached from the conviviality around him; I whispered that mom couldn’t get her breath. He followed me, in his lanky lumbering way, to the kitchen.

My petite mother sat bent over, head down, her shoulders heaving. She wore a blue double-breasted jacket with a white turtleneck, a jaunty scarf at the neck and a festive Christmas tree broach on her lapel. She’d been so lively earlier. Now she was distressed. She couldn’t get the hang of the inhaler. “Breathe out, Mom,” I said. Then, as I lifted the inhaler to her mouth: “Now breathe in as deeply as you can.” She took a shallow sniff and then exhaled, coughing. It was hopeless. “Maybe I’ll be OK if I just sit here,” she said between pants. “You go and be with your guests.” I held her wrist, trying in vain to take her pulse. Her skin felt clammy. I asked her if she felt dizzy and she nodded weakly.

Just an hour before, my mother had repaired to our unheated porch to smoke a cigarette. I’d followed her out into the cold to wrap a quilted jacket around her shoulders and to switch on a small space heater. As she’d opened the oaken front door, wielding her pack of cigarettes and a glass of wine, she’d smiled in an impish but also sheepish way at the friendly tsking from A’s sister; I’d said, “I agree completely, I wish she’d quit, but what the hell, she’s 81 and still kicking, so at this point …”

Still, even then I recalled my shock the previous summer when my mother had to stumble to a bench, nearly breathless, as I walked with her from a restaurant to the car in a brisk wind. She’d walked at a snail’s pace from the start; my father and A. had soldiered ahead and were already opening the car doors as I huddled next to my panting mother on a wooden bench 40 yards away.

My mother saw the worry register on my face as I took in her ragged huffing. “I know you’re alarmed because you haven’t seen me like this,” my mother managed to pant out. Just minutes before, she’d been dragging on a cigarette, having lit up, as always, the moment she stepped free of the restaurant’s smoking ban. “Do you have pneumonia again?” I asked her.

The truth was that I didn’t see much of my mother. We’d long settled into a groove of casual intermittence: Brief phone conversations every couple of weeks, a handful of visits (Thanksgiving and Christmas, a few group birthdays, plus a dinner when my parents returned from their winter elderhostel soujourns … and the occasional night out, like this one at a restaurant in the city). I knew, though, that my mother had become easy prey for respiratory woes: bronchitis twice a year on average, sometimes morphing into pneumonia. The past winter, she’d landed in a hospital in Arizona; the previous year, it had happened in Florida—episodes my sister and I had learned of only after the fact.

Her doctor, my mother told me that night, had diagnosed in her “a touch of emphysema.” My mother now had some white powdery medicine she took; she pawed through her her purse to show me the Advair tablets. “Emphysema!” I exclaimed, peering at the little foil packets of powder. But she waved her hand dismissively: “It’s not anything dire,” she said, still breathing heavily. “I just have to take this stuff every day.”

“But what exactly did the doctor say?” I asked. My mother was dabbing at her nose with a kleenex. Her breathing had begun to steady. “She said the same thing she always does: Get. Rid. Of the cigarettes!” she said, with exaggerated dramatic emphasis and a flourish of her left arm.

“I’ve tried,” she added in a vaguely bemused tone. I knew that was true. It just never took; within days she was cheating, half a cigarette in the morning, half at noon, a whole one after dinner, then back to a pack-and-a-half a day. She was hooked but good, she said. She should have quit when she was 19 and her father offered her $100 to ditch her Lucky Strikes.

I’d always thought smoking took the edge off her life, the everyday letdown and slog of it; but sheer drug addiction also had to be ferocious in someone who’d been smoking for 60-odd years. Nicotine, rolled into tobacco with a hundred other carcinogens; all that we know now. My mother had started in college, during the World War II years when when cigarettes were sexy, when everyone lit up in supper clubs and movie houses, when Camel was advertised as “the choice of more doctors.” I thanked my stars I’d been able to stop two decades before; I still worried about the damage my 12 years of Vantage 100s might have wrought.

“You’re lucky you were able to quit,” my mother said then, as though reading my mind. “I wish I’d never started the stupid things.” She was getting to her feet. “I’m OK, really, Mia. Your old mother isn’t going completely to pot yet.” She gestured toward the parking lot. We could see a plume of exhaust; my father had started the car.

“We’d better catch up,” my mother said. “He’s antsy. I’m sure he’s getting annoyed.”