Part-way through this memoir of hospice medicine and living with loss, Rachel Clarke lists a few troubling ideas she prefers to avoid thinking about: global warming, far-right populism, email overload, menopause, declining numbers of bees and, of course, mortality. It’s become a truism that western societies have difficulties accepting death, but Clarke, whose daily work is to ease the suffering of the dying, has a different view. She sees sense in avoiding the contemplation of death, and often applauds her patients for it – right up until they no longer have any choice.

It’s a kindness to see death as belonging on the same list as brown envelopes from the government: “Maybe, more prosaically, dying is on a par with tax returns and pensions. We know we should address them all proactively, it is just that the admin involved is, frankly, tiresome.” Only 4% of the population have had the foresight to prepare an “advance directive” detailing how they’d like to be treated or left in peace should they become critically ill; Clarke would like to see that number increase. Her book has an appendix of websites and organisations that can help. But Dear Life is not a manual for dying, or an orthodox medical memoir – it’s a very personal autobiography. It charts one woman’s trajectory from a happy childhood in rural Wiltshire as the daughter of a local GP, through university, then into a successful career making TV documentaries in London. There’s a Damascus moment in her late 20s when she decides to retrain as a doctor, first in acute and emergency medicine, then finally as a consultant in palliative care.

As a child Clarke’s first encounter with death was a teacher obsessed with Mutually Assured Destruction. There were rope-swing accidents, a teenage wipeout in a car; in 1999 she was out for a drink in Soho when a bomb ripped through Old Compton Street. Clarke remembers walking towards the pub, then finding herself face down on the road. “A few feet in front of me lies a body in the gutter. Dimly, I clock how bright the man’s blood is, and that his leg, neatly severed, lies on the ground beside him.” Slowly she picked herself up and staggered off between the casualties, still deafened by the blast. “It had not occurred to me to try and help any of them,” she admits with candour, regret and guilt. “You could put this down to shock, but I know that the truth is, even had I been in a state to help others, I would not have really known how to.”

As a TV film-maker Clarke endured leering and abusive bosses, and as a medical student comparably insufferable seniors who delivered bad news without care (“either the consultant was oblivious of the devastation he had just unleashed, or else he was running away from it”). No one wants their doctor weeping at the bedside, and she elegantly explores the highwire balancing act at the heart of medicine and nursing: how to be detached enough to be useful, while maintaining enough human sympathy to be kind. It has become fashionable to emphasise the importance of caregivers’ humanity over their technical competence but, refreshingly, Clarke is having none of it: “Should a family member of mine suffer a cardiac arrest while in hospital, I want only one thing at their bedside. Cold, hard, technical prowess … I do not want humanity if it comes cloaked in indecision.”

It’s halfway through her book that her story turns to palliative medicine. “Despite my love of acute and emergency medicine, I found myself drawn to patients with life-limiting illness precisely, in part, because some other doctors ran a mile.” Chapters such as “Wonder”, “Light in the Dark”, “Clutching at Straws”, and “Gratitude” tell empathetic stories of Clarke’s encounters with the dying, and bear witness to “people rising to their best, upon facing the worst”. There are deathbed scenes, funerals and even a couple of weddings. There is none of the cynicism or dark humour that drive Adam Kay’s medical memoirs; the drivers of Clarke’s narrative are instead the joys and consolations of teamwork at the sharp end of life as it fades, and her relationship with one dear life in particular she’d like to hold on to: her father.

Dr Clarke senior was frequently called out of his bed to emergencies at night, and away from family weekends – the decency and worth of his vocation seemed to Clarke an inspiration. He remained a guiding presence throughout her life, offering perspective down the phone whenever Clarke needed to talk. When, in his 70s, he was diagnosed with bowel cancer, those father-daughter calls took on a professional air – at first, with clinical dispassion, they discussed his tumour’s spread and its potential treatments. Though she’s had her own brushes with cancer, it was only with her father’s decline that Clarke realised how breezily she has been engaging with the loss of others. As someone living and working in such proximity to the dying she’s long been aware that “losing a loved one hurts precisely as much as it should do”, but her father’s death prompts an epiphany that she hopes will, despite the pain of it, make her a better doctor. “All those years of medical training, I now know, have singularly failed to equip me with proper insight into the magnitude of other people’s grief.” Working in palliative care is not, as some assume, a depressing job – “nothing could be further from the truth”. Instead it offers the opportunity to work daily with the best in human nature, and see first hand most people’s courage, compassion and capacity to love.

Many readers will know Clarke as a vocal and effective political campaigner: she was a prominent critic of Jeremy Hunt through the junior doctors’ strike, and continues to be as damning of Matt Hancock and the Johnson administration. One strand of Dear Life illustrates just how woefully underfunded NHS care has become and how, as a consequence, short lives are being further shortened. She characterises the patchy lottery of palliative care provision as “a national outrage, not to be rose-tinted. If ever an index of humanity mattered, it is surely how generously a society chooses to care for its most vulnerable members, those for whom death is approaching”. Our shrunken, cash-starved hospitals have necessitated the rise of a new speciality, “corridor medicine”, in which it is assumed that most critically ill people won’t find a place on a ward but will be cared for instead on a trolley off A&E.

Clarke recounts a conversation with an exhausted colleague who patrols those corridors, looking for people who might warrant a rare bed in the intensive care ward – this, in the world’s sixth richest economy. “‘It’s beyond inhumane,’ he mutters flatly. ‘I was literally playing God, choosing who will live or die.’” In moments like this Dear Life is a heartbreaking, exhilarating read: Clarke shows that such choices are a vital but small part of medicine. Like taxes, death is notoriously inevitable; a truly humane society would be concerned not just with when it happens, but how.

• Gavin Francis’s Island Dreams: Mapping an Obsession is out in May. Dear Life: A Doctor’s Story of Love and Loss is published by Little, Brown (RRP £16.99). To order a copy go to guardianbookshop.com. Free UK p&p over £15.

• This article was amended on 16 February 2020. A document detailing a person’s treatment preferences in case of critical illness is known as an “advance directive”, not an “advanced directive” as originally stated.