After the war correspondent Marie Colvin was killed in Syria in 2012, I set out to write her biography, with the aim of bringing my friend back to life. Seven years on, as a feature film about Marie is set to open, in the wake of last year’s documentary chronicling her last days, I wonder if instead I’ve been party to the creation of a myth.

Since the biography was published, a stream of young women have told me, either in person or on Twitter, that they see Marie as a role model. Many aspire to be journalists or have already started out. “Thank you for immortalising Marie Colvin, journalist war heroine,” wrote one. Although I would never discourage anyone from following a trade that has absorbed and thrilled me all my life, I nonetheless feel uneasy. In an age of celebrity, people are drawn to those who achieve fame and glamour, but without dwelling on the personal cost.

Marie and I would meet in war zones, or during revolutions or uprisings, she covering the story for the Sunday Times and I for Channel 4 News. We never saw ourselves as any different from our male colleagues, yet by writing about her I had stepped on to treacherous ground: from Lee Miller and Martha Gellhorn in the second world war to Kate Adie and more recent incarnations, women war reporters have always attracted a certain fascination.

Marie, of course, fascinated more than most. She was a charismatic figure, known by her trademark eyepatch, which she wore after being shot crossing a front line in Sri Lanka in 2001, losing the sight in her left eye. Even before that, she had cheated death in Lebanon, Kosovo and Chechnya.

As I wrote about her life, part of me wanted to debunk the myth of the glamorous woman in the war zone. But then I was confronted with the reality of Marie, one week tramping through snow and mud in the mountains of Chechnya in fear for her life, and the next chatting to Warren Beatty at an LA party. I understood that the glamour hid pain, but where did the balance lie? Her courage was never in question — Marie tended to go in further and stay longer than other correspondents — but her judgment could be. As she herself once asked: “What is bravery and what is bravado?”

Treading that line helped to make her reputation. In 1999, during the violence that followed the independence referendum in East Timor, she stayed in the besieged UN compound when most reporters left for Australia on the orders of their editors. Militiamen, some of them Indonesian soldiers in disguise, threatened to overrun the compound and kill both the terrified Timorese who had sought protection there and any foreigners.

When Marie called her editor to say she was staying behind with two Dutch journalists, both women, he asked where the men were. “They’ve gone,” Marie replied, adding, “I guess they don’t make men like they used to.” It was a classic Marie remark, and slightly unfair, because at least two male journalists had gone into the hills with the Timorese guerrillas. Marie’s eye-witness reporting of the desperate situation of the Timorese put huge pressure on the UN and world governments. Eventually, the Indonesians called off the militia and agreed to admit an Australian-led peacekeeping force. “I embarrassed the decision makers and that felt good because it saved lives,” wrote Marie. “It is rare to see such a direct result in journalism.”

The film A Private War tries to show the real woman behind the myth, but by definition, if they make a feature film of your life, you become a legend. Rosamund Pike — a blonde, willowy English rose — might seem like an unlikely candidate to play Marie with her dark curls and earthy chuckle, but her portrayal is spookily accurate. After studying YouTube clips of interviews Marie gave and video reports she sent back for the Sunday Times website from Libya during the 2011 revolution, Pike mastered Marie’s 20-cigarettes-a-day gravelly New York drawl and the angular way she moved her arms.

Yet a feature film is very different from a biography. Marie did not, in real life, go around war zones telling everyone that she was writing the first rough draft of history. Only a tiny part of covering a war is action of the kind depicted in the movie — most of the time one is waiting for something to happen, or failing to get to the right place (and worrying that the competition is already there). And, knowing quite a few sceptical British newspapermen including the one in question, I can’t imagine Marie’s foreign editor at the Sunday Times, Sean Ryan, referring to her as “our very own living legend” at an awards ceremony.

After being hit by a grenade in Sri Lanka, she joked: ‘All I want now is a cigarette and a vodka martini’

The Sunday Times did, however, build Marie’s “brand”, prominently displaying her photo byline with eyepatch, and emphasising the risks she ran to get her stories of civilian suffering in war. Waiting for surgery on her eye after being hit by the grenade in Sri Lanka, she joked with Ryan: “All I want now is a cigarette and a vodka martini.” He added the line to the end of her copy.

To some extent Marie bought into the myth being created for her. Ultimately, though, she couldn’t reconcile her image as a fearless war correspondent with the doubt and pain she felt inside. She was haunted by images she could not un-see: an old man with rasping breath in Chechnya with the back of his head blown off by a Russian rocket; the body of a peasant dressed in a worn woollen suit that she came across under a bush in Kosovo; a young Palestinian woman she watched die from gunshot wounds in Beirut. She found it hard to admit to the terrifying nightmares and sense of unreality she experienced, but eventually, in 2004, she was diagnosed with post-traumatic stress disorder.

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I first encountered Marie in 1998, covering the Ethiopian-Eritrean war, and we saw each other often in the years that followed. She confided in several female friends about her PTSD but not in me — we didn’t have that kind of intimacy. If we had, I doubt that I would have been able to write the book. “Like any proper biographer,” wrote the late Francine du Plessix Gray in the introduction to her book about her parents, “I strove for a compassionate severity, for [a] balance of ruthlessness and tenderness.” That was my aim, too — to show Marie with all her flaws, “trailing clouds of glory and pandemonium” as Katrina Heron, her close friend from Yale, put it.

I wrote at length about Marie’s problems with alcohol. Although she was professionally successful, had a supportive network of close friends and a life she enjoyed in London, she was often unhappy and at times despairing. Her last boyfriend, Richard Flaye, told me that sometimes when he stroked her, he would feel tiny, sharp pieces of shrapnel accumulated over a lifetime working their way out of her skin. It was as if her body was trying to rid itself of all the horror she had experienced.

That, then, is the danger of the myth of Marie. What bothers me is not that she went too far to get the story but that she was careless with herself, both her body and her mind. Her story is not just exemplary, but also cautionary. These days, editors are far more aware of the dangers of PTSD, but young journalists, often freelance, determined to make their name, may still underestimate the toll the life may take on them. Not all war correspondents are traumatised or injured, but many find it hard to maintain stable relationships. Marie’s private life was a war zone, just like the conflicts she covered — there was nothing glamorous about her suffering.

In writing the biography of a fellow journalist I have committed what is regarded as a crime in our trade: making one of us the story. But Marie was exceptional as a person as well as a reporter. I tried to capture her joyful, chaotic spirit, with her inability to read a map or work a satellite phone, and her way of telling stories that made you weak with laughter. But, maybe inevitably, readers focus on her derring-do in war zones and her doomed love affairs. I concluded that, however honest I was in my portrayal of Marie, I couldn’t control people’s reactions to such a big life, full of experiences entirely exotic and extraordinary to most people.

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In February 2012, Marie and I had dinner in Beirut, before she was smuggled across the border into Baba Amr, a rebel-held enclave in Syria — a risk I had deemed beyond my danger threshold. There, she interviewed people in the “widows’ basement”, where women and children were sheltering under artillery fire from the Fourth Division of Bashar al-Assad’s Republican Guard. Her story gave the lie to Assad’s claim that everyone there was a terrorist.

That, however, was not enough for her. Expecting a government takeover of the suburb, the rebels forced the journalists to leave but Marie, feeling she had abandoned the people of Baba Amr, decided to go back. It was a fateful choice, and one that ensured that she would become a symbol of the risks journalists run to get the story. As her life story was told and retold, it would also make her a legend.

A Private War ends with the camera lifting high over the ruins of Baba Amr, leaving below Marie’s body and that of a French photographer, Rémi Ochlik, who was killed in the same artillery strike. (Last week, the US District Court of Washington DC found the Syrian government liable for $302m in civil damages for Marie’s murder.)

In my mind’s eye, I see Marie, in her grey jeans and blue sweater, hair pulled into a black scrunchie, rushing out of the door of the damaged building where she had been sleeping, leaping forward as the rocket hits, notebook in hand, frozen in motion, pushing on to the next story. For me, she is not a myth but a friend, lost forever.

Lindsey Hilsum is international editor of Channel 4 News and author of ‘In Extremis: the Life of War Correspondent Marie Colvin’

‘A Private War’ is released on February 15

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