I watch my 88-year-old mother’s gradual decline and see her reaching for memories sometimes as if they’re a glimmer on some distant horizon.

My mother has Alzheimer’s, although it has been kinder to her than to many. She exists mainly in what seems like a kind of confused but contented daze. She is not agitated or distressed, and she appears always genuinely pleased to see one, perhaps because she can’t remember that the last visit was only yesterday.

For the moment she’s still Mum. Her character remains present. On occasion there’s a girlish laugh, a spark of delight or amusement in her eye. She can still let slip an astute remark or a sharp observation. So something continues to nourish her personality; and perhaps that something is a set of internal stories, known only to her. Even so, I sense that her stories are dimming, and when they’re gone, if illness hasn’t claimed her by then, what will be left of her? Perhaps only the stories we tell about her.

In Spain, by contrast, we had three sprightly 80-year-olds on the course we were running, the week before last. An Israeli photographer, the wife of a naval officer, and a retired therapist, they brought to the 10-strong group an energy that we haven’t previously encountered since starting The Stories We Tell.

It was as if they felt less urgency to share and more inclination to listen and reflect; as if the stories with which they each brimmed were mulching down into some kind of rich compost on which they could draw for insight. They brought with them a certain reassurance that I believe was felt by the rest of the group. And they reminded me that not all octogenarians are destined to share my mother’s decline.

It was a magical week. The centre, Cortijo Romero, is hidden away in the Alpujarras, the valleys that crease the foothills of Spain’s Sierra Nevada. The gardens and courtyards were in bloom with bougainvillea and hibiscus and fruit-laden orange trees. Tall palms stood around the pool, from which one could look up to the snow fields of Mulhacén, Europe’s highest mountain outside the Alps.

The room we used was cool and spacious with a flat, raftered roof that served as a platform for early morning yoga and tai chi, and offered long views out to the mountains and the white villages, once peopled by the Berbers, that cling to their upper slopes. On a level below, at the end of an orchard and lawn, was a circular meditation room with perfect acoustics. We gathered there on the final morning to sing, with mesmerising effect.

We shared the centre with a party of walkers with whom we mingled over the evening meal, a regular vegetarian banquet. Their company and their tales of the day’s sorties into the mountains offered relief, for those who needed it, from the intensity of the storytelling bubble in which we had spent a good part of the day.

This is what we do when we come together. We tell stories. Even if we’ve been telling them all day, we do it again come the evening. We can’t help it. And when we can’t tell any more, we listen. There is something in the atmosphere at Cortijo Romero that puts oil in a storyteller’s lamp.

‘I am a giant wandering assemblage of memories,’ says the writer Neil Gaiman. ‘They define me. I wouldn’t want to take the forgetting pill, or lose any of them.’ Some people, like my mother, have had the forgetting pill thrust upon them. Those luckier ones of us who haven’t must make the most of them, and learn what we can from them before it’s too late. Our octogenarians at Cortijo Romero were an example to us.