Theresa May speaks at an EU summit in June 2017.Geert Vanden Wijngaert / AP

For the past two years, the debate over Britain’s withdrawal from the European Union has focused on the costs and benefits of trade, the effects of immigration, and the frustration of communities left behind. Yet when the full story of Britain’s departure from the EU is told, it will be in large part the tale of a passionate relationship between one woman and her political party.

For more than two years, British Prime Minister Theresa May has sought to balance the needs of her country, as she negotiates its exit from the European Union, with that of her party, wherein a fiercely Eurosceptic wing has limited her ability to compromise. Now, with Brexit fast approaching at the end of the month, and May’s attempts at an amicable divorce lacking parliamentary support, the prime minister can choose to delay the withdrawal, currently set for March 29, or lead Britain out of the EU with no deal, which detractors say could leave the country without food, without medicine, without international travel.

So the question is this: Will May drive her country off the precipice and abandon the EU without a cushion, or risk splitting the political party that—perhaps more than any prime minister since Edward Heath, the man who took Britain into what is now the EU in the first place, nearly a half century ago—she has made the center of her life?

May came to politics early. An only child growing up in rural Oxfordshire in the 1960s, she was inspired not by the anti-establishment spirit of the age, Vietnam War protests, or rebellion in the streets of Paris, but the quiet conservatism of her neighbors. With few close friends to distract her, she joined the Conservative Party and, by the age of 12, had decided to make politics her future.

So deep was her dedication that when her father, Hubert, a Church of England minister, warned her off alienating parishioners who did not share her views, May agreed to confine her activities to stuffing envelopes in a back room. Even the boredom of spending her Saturday afternoons alongside the village matrons in the local Conservative Party office did not deter her.

May met her future husband, Philip, while they were both students at Oxford University, at a dance organized by the student Conservative association. In the 1980s, the two spent the early years of their marriage serving the party in south London, she as a Conservative local councillor and he as an unelected branch secretary. In the 1990s, they traveled the country as she sought to become a member of Parliament. They had few close friends, and both May’s parents had died by the time she was 25. With steady but not particularly inspiring banking careers and, to their deep regret, unable to have children, the Mays made politics the focal point of their life.

Not until 1997 did May finally enter Parliament—as many of her fellow Conservatives were being voted out in favor of Tony Blair’s Labour Party—but it would take another 13 years of slogging in opposition before the Conservatives returned to power. Under David Cameron’s leadership, May reached the highest level of the cabinet, as home secretary.

At the Home Office, May finally received the respect many of those who have worked closely with her say she craves. While the post—which is responsible for a bewildering array of issues from immigration to internet safety, as well as the police—had a reputation of being a political graveyard, May thrived, surviving for six years, the longest run in decades, ending only because she became prime minister.

Many attribute her success as home secretary to an innate pragmatism and a stubborn streak, both boons in a role that requires quick thinking and forceful decision making. She provided strong leadership during a series of terrorist attacks; resisted American pressure to extradite a British national for hacking into the Pentagon, while insisting on it in the case of a radical Islamic preacher accused of terrorist offenses; and oversaw deep cuts to police budgets and staffing numbers.

Her cabinet colleagues often found her intransigence frustrating, with a Conservative MP labeling her “a bloody difficult woman” in a hot-mic recording. But the clashes were not ideological. Beyond a belief in meritocracy—a “level playing field” as she likes to describe it—May’s ideas about what she would like the world to look like are difficult to discern.

While her combination of pragmatism and stubbornness served her well at the Home Office, those characteristics are perhaps less useful in a prime minister, a role in which a sense of vision and an ability to compromise might be more valuable. That is particularly true in May’s case; her desire for a sensible Brexit deal collides with the ideological determination of a chunk of her party for a symbolic rupture from the EU.

May’s dilemma is not a new one. Britain’s relationship with Europe has come close to tearing the Conservatives apart for 50 years. It brought down a series of prime ministers, usually as a result of pressure from the Eurosceptic right. Most recently, Cameron hoped to relieve some of this pressure by agreeing to demands for a referendum. May campaigned alongside him, albeit somewhat reluctantly, to remain in the EU, but when Britain voted to leave, Cameron resigned.

In the ordinary scheme of things, it probably would have made sense at that point, in the summer of 2016, for a dedicated Leaver to take charge of both the Conservative Party and the Brexit process. But with the Leavers proving woefully incapable of leadership—May’s rivals all imploded spectacularly during the contest to succeed Cameron—she found herself unopposed and, as her actions soon suggested, with a profound sense of gratitude to the Brexiteers for giving her the job she had long coveted.

Determined to both avoid the fate of her predecessors and keep the party together, she took a series of steps, including inviting her party rivals to serve in senior positions, that suggested to the Brexiteers she was on their side and committed to leaving the EU on their terms. When this strategy clashed with the realpolitik of negotiations with the bloc, May was stuck. Her practical solutions proved unacceptable to many MPs from her own party, and to those from the Democratic Unionist Party, the Northern Irish grouping on whose support her government relies.

After it became apparent some months ago that May could never sign the Brexiteers up to a deal that would be simultaneously acceptable to the EU, many began to hope she would look beyond her party to like-minded people on the opposition benches. This would probably have involved agreeing to a softer Brexit than she had promised but, the argument went, the resulting agreement would be the better for it. The outcome, however, would likely be a Conservative split—something she could not bring herself to allow.

And so the drama continues, as May insists her deal is the only way to avoid a no-deal Brexit. Britain is still officially due to leave the EU in a matter of weeks. And while the date may be pushed back, unless MPs can agree among themselves, and with the rest of the EU, on what form a deal will take, Britain will leave without an agreement.

Anyone seriously expecting May to square the Brexit circle by following the example of Ramsay MacDonald—the Labour prime minister who abandoned his party to form a national government with the Conservatives during the Great Depression—fails to understand her motivations. The teenage girl who stuffed envelopes in a back room, the middle-aged woman so thrilled to be Conservative leader, could not possibly abandon her true love now.

Will Theresa May choose heart over head and allow the United Kingdom to crash out of the European Union? Everything in her history suggests she’s capable of it.

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