The clarity of hindsight is often overstated, particularly when it concerns the relationships that transform us. The English teacher who taught us King Lear somehow becomes the sole reason that we write; our first big love opened us to the world; our childhood barber is the reason we smoke. But at times in our lucky lives, it is possible to know what you have while you have it. I learned this from someone who’d spent a lifetime trying to accurately perceive what was in front of her. For nine years, I worked as a personal assistant to the titanic Joan Didion. Joan was in her 80s, I in my early 20s, and for a good chunk of the time I worked for her, I lived with Joan in her apartment on the Upper East Side in Manhattan. We were, to outsiders, an odd pair: Joan, tremendously frail in her small, birdlike body, quiet, exacting; I, on the other hand, tall, excitable, eager to prove my worth, still in the process of self-discovery. Day by day, we sat together and read poems and the newspaper, listened to music, smoked. Day by day, she was teaching me how to sit still, to be watchful, to be present. When you are friends with someone 60 years your senior, you learn quickly that this moment – this exact moment – might be your last together. Before I met Joan, I was hardening against the world. I had been made fearful by the shocking death of a close friend, angry by personal family trauma and embittered because of the political and economic realities of the US during and after the recession. Joan on the other hand, like many people in their 80s, had already lived through unspeakable loss. Her husband and daughter had died within 20 months of one another. She’d lost family members, dear friends, colleagues she’d counted on. Joan might have preferred a host of loved ones long gone to keep her company in her final decade. But she grew old and needed help. A friend of Joan’s, a fellow writer who was my teacher at the time, put us in touch. What might have lasted a week instead became a near-decade-long relationship. During this last segment of Joan’s life, she was still able to remain open, and present, to see what was in front of her. Tragedy and grief were, to her, part of the landscape of the living; loss did not crowd out all other emotions or endeavours. Joan taught me that it was intellectually lazy to allow grief and anger to envelop the entire landscape. The real work of a writer’s life – of a person’s – was straining to keep all things in view all at once, so that grief, joy and work could have their proper place. I was in Joan’s orbit for nine years, a fraction of her existence, but the bulk of my own adult life. I learned from our unconventional friendship that the events of our lives do not ever disappear or drop away; instead, as we accrue more experiences, memories and loves, our lives widen and deepen. Past traumas or victories that once seemed outsized, even immovable, do not disappear; they simply concede space as new feelings and joys arrive. There is a belief – mistaken in my view – that our elders have sunk further into themselves, weighed down by the accumulation of tragedy and loss, estranged by displacement from their time and culture. Joan, instead, preferred silence to inexactness. When one had the great fortune of knowing exactly what one wanted to say – for instance, I love you, or, why don’t we have chicken? – one simply said it. Sometimes, it was enough to be together for a moment in unbroken silence, the silence somehow closer to the unspeakable truths of our lives. Our relationship was, of course, haunted by the palpably real end-date hanging over it. Towards the end of her life, there were dips, recoveries, and many middling periods. Whenever I was not with her and my phone rang, I feared the worst. And so perhaps the greatest gift of a friendship with someone 60 years your senior is also the worst part of the relationship. With our contemporaries we are able to embrace the delusion that our time together is limitless – with Joan, no such fantasy was available. Instead, there was a mandate, a moment-by-moment command from the holy and metaphysical that instructed: “Do not miss this. Do not overlook a single thing. This might be your final moment together.” Cory Leadbeater is the author of The Uptown Local: Joy, Death and Joan Didion