Henry Lyulph Holland, 1st Earl of Shane, had existed for so long that the public had begun to regard him as immortal. The public, as a whole, finds reassurance in longevity: the long-liver has triumphed over at least one of man’s initial handicaps: the brevity of life.

The opening lines of Vita Sackville-West’s novel All Passion Spent pulls me right back into my Hogarth Press edition. When I first read it – 30 years ago – some passages were lost on me: ‘Earl of Shane, KG, GCB, GCSI, GCIE, etc etc. – his diminishing honours trailing away behind him like the tail of a comet’, but I understood 88-year-old Lady Shane who, after seven decades devoted to the demands of her husband and children, finally, in her widowhood, chooses to live independently in a tiny house in Hampstead.

Years later, I learned from Victoria Glendinning’s biography that it was Vita’s mother-in-law, Lady Carnock, who gave her the idea for the novel. Lady Carnock had clung tenaciously to the family home; Lady Shane in the novel does what Vita thought Lady Carnock ought to have done.

Back then I didn’t understand the tribal procedure of aristocratic primogeniture. I was more familiar with ordinary mortals who create a home and garden that they occupy for life, but literature and history led me to the world of the nobility and demi-nobility who are merely the stewards of their great houses. When the sons inherit, mothers must move on, sometimes into the dower house a discreet distance from the main house, sometimes into a cottage converted to her taste, occasionally a modest flat near Peter Jones.

At first these evictions seemed heartless to me but I’ve now lived long enough to witness close-up widows who have resisted all the machinery of the siege that emotion can bring to bear, refusing to be dislodged even when their own children and grandchildren are living in cramped keeper’s cottages. These women wander in solitary splendour through a Christo-like universe of acres of dust-sheets, imposing an out-of-date formality on daughters-in-law and grandchildren. By clinging on, they are saying ‘I am more important than the history of this place and its future,’ thus depriving the estate of the sunlight, oxygen, fun and rigorous energy – economic and emotional – needed to keep old houses alive. With agricultural income on the wane, estates have had to reinvent themselves but the effort needed to produce income – to create music festivals, literary festivals, farm shops, gift shops, garden festivals – is huge and barely makes a dent when it comes to reroofing and rewiring.

Because these things are so hard to say (‘Mummy, have you ever thought . . . ‘), maybe what’s needed is a slender volume the size of a prayer book. It could be called The Good Good-bye (ideally, written by Lady Tottering), with chapters on when and how to move out, preferably not at knifepoint. The first chapter should be on the pleasure of choosing and renovating the dower house before you are dowered and then take only the most cherished possessions: the best furniture, one set of favourite china, the most-loved paintings, so that everything is distilled to its essence, moving from quantity to quality. Until this book appears, you’ll have to go to Heywood Hill for a copy of All Passion Spent. Its fierce simplicities still have the power to inspire. Read it, then send your copy to whom it may concern.

This article first appeared in Country Life magazine on June 30, 2005.