Merkel's troubles started with a bitterly disappointing election result in September. They grew when her first attempt at forging a new government collapsed in November. And they have been compounded in recent days, as polls have shown German voters tiring of her leadership.
Merkel now has what many regard as a last shot to cobble together a coalition and ward off an embarrassing electoral do-over that could see her lose her grip on power.
"Time is running out," said Stefan Kornelius, a Merkel biographer. "She is under immense pressure to somehow make this happen."
But even if she succeeds, significant damage has already been done. Once regarded as invincible, Merkel is suddenly vulnerable in a way that has shifted the German political conversation to a topic long whispered about but rarely publicly debated before: Who should come next?
There are many contenders, their names bandied about in German newspapers and magazines in recent days. But Merkel's saving grace — for now, at least — may be that there is no obvious successor.
There's certainly no one who could immediately fill the outsize role that Merkel has played in global affairs. Though not always willingly, the low-key East German with a PhD in quantum chemistry has become de facto leader of Europe and keeper of the flame for those who regard President Trump's brand of politics as a threat to core Western values.
"The world is engulfed by Trumpism and populism and vulgarianism," said Kornelius, a journalist with Munich's Süddeutsche Zeitung newspaper. "The alternative is not even visible anymore. Merkel has to prove that the alternative can still exist."
She might not have the chance.
Over her dozen years in office, Merkel has guided Germany to robust economic health, with strong GDP growth and low unemployment. Her decision to welcome more than 1 million asylum seekers in 2015-2016 galvanized the far right but was supported by the political mainstream. She has navigated a series of European crises, from the war in Ukraine to Greek debt.
Before the September elections, political observers had widely assumed that Merkel would once again coast to victory, with a clear shot at matching the record 16-year tenure of her onetime mentor, Helmut Kohl.
Instead, her center-right Christian Democratic Union (CDU) suffered its worst result since 1949, including the loss of a million of its voters to the far-right Alternative for Germany (AfD) party.
While the CDU still came out on top of a fractured field, Merkel was forced to pursue an unwieldy deal among her own conservative bloc, the pro-business Free Democrats and the environmentalist Greens.
When the Free Democrats unexpectedly backed out, Merkel had to go to plan B: a revival of the grand coalition between the center-right and the center-left that has governed Europe's largest economy for the past four years.
Substantive talks are only now getting underway, with a deal not expected before April, if one comes at all. It's already the longest that postwar Germany has ever gone after an election without a government.
Although voters didn't initially appear to blame Merkel, polls suggest she has increasingly become the target of frustration with the very un-German gridlock and dysfunction.
A survey published by the Bild newspaper in late December showed that nearly half the country did not want her to complete a fourth term. A poll released days later by Die Welt had even worse news for Merkel: Nearly half the country would like her to step down right away.
"She is tasked with putting together a government, and she hasn't done it," said Thomas Kleine-Brockhoff, director of the Berlin office of the German Marshall Fund and a former presidential adviser. "There's a failure on her side that the constitution attributes to her and that the people seem to attribute to her."
More than that, Kleine-Brockhoff said, Merkel's core argument for staying in power may be fraying. The 63-year-old has long positioned herself as the guarantor of stability for a country that highly prizes that quality.
Yet, in the current talks, he said, her presence may be destabilizing.
The Social Democrats, the government's would-be junior partner, are desperate to get rid of Merkel. Her tenure has corresponded with a free-fall in the party's popularity as the chancellor has shifted to the center and co-opted the Social Democrats' core issues. The party's rank and file will have to approve any deal, which could prove a hurdle.
Even Merkel's own party, which has long been disciplined in supporting her, may have a reason to see her go early, since it will want to ensure an orderly transition to her successor.
"We will be seeing the last period of government for Angela Merkel, and it will be heavily influenced by, if not overshadowed by, the question of succession," Kleine-Brockhoff said.
Although leading politicians from the CDU and its Bavarian sister party, the Christian Social Union (CSU), have generally been circumspect about their desire for the top job, that's beginning to change.
Jens Spahn, a 37-year-old who is considered a rising star on the CDU's right flank, has urged Merkel not to give an inch in talks with the Social Democrats and for the CDU and CSU to form a government on their own if negotiations fail.
But there may be some self-interest in that advice: Without a stable coalition government, Germany could be forced to hold new elections far earlier than planned, perhaps as soon as this year. And it's unclear whether Merkel would lead her party in another vote.
"That's a secret that's hidden in her heart," said Jürgen Hardt, a veteran CDU member of Parliament and the party's spokesman on foreign affairs.
Hardt said there is no question that Merkel should remain as chancellor and have the opportunity to lead a new coalition government.
"There's no one else who is able to get so much support from the Bundestag and from the public," Hardt said, referring to the German Parliament.
But Hardt also said it was time for Merkel to promote possible successors and to allow a younger generation to prove itself.
"There are too few new faces on the political scene in Germany," said the 54-year-old Hardt. "The CDU and the CSU have to be aware that, sometimes, politics is about presenting something new."
It has been a long time since Germany has done that. Of the world leaders who have stuck around as long as Merkel, most are autocrats who resort to iron-fisted tactics.
Merkel, if anything, has positioned herself as the anti-autocrat — a defender of traditional democratic values at a time when those are seeming evermore outdated.
If she leaves, said Jürgen Falter, a politics professor at the University of Mainz, "it would weaken the European Union, and it would weaken those who want the West to be led in a more rational way than Trump is able to do."
Already, Merkel's voice has been more muted on major European matters, including Britain's European Union exit and euro-zone reforms initiated by French President Emmanuel Macron. Although she continues to lead a caretaker government, it cannot make any significant moves until the parties reach a coalition deal.
With months of talks probably still ahead, Merkel has struggled not to show impatience with a process that she surely knows is sapping German influence, and her own, by the day.
"The world," she told the nation in her traditional New Year's Eve address, "will not wait for us."
Rick Noack contributed to this report.