When Hope Hicks walked into President Trump’s private study on Wednesday to inform him that she planned to leave the White House — concluding a can’t-make-it-up run in which Ms. Hicks, a woman with zero political experience three years ago, became the closest aide to the most powerful man in the world — the president responded like a father whose daughter had outgrown the nest.
According to a person with knowledge of their conversation, Mr. Trump expressed an understanding of Ms. Hicks’s desire to pursue a new phase of her life. But, the person added, he also acknowledged something else: that Ms. Hicks’s happiness in her role had begun to wane lately, after a trying few weeks in the public glare.
The departure of Ms. Hicks, arguably the least experienced person to ever hold the job of White House communications director, capped an astounding rise for a political neophyte whose seemingly implausible career hinged on a deep understanding of, and bottomless patience for, her mercurial charge.
But as someone with a pull toward discretion — Ms. Hicks, 29, who grew up in the buttoned-up suburb of Greenwich, Conn., the daughter and granddaughter of prominent public relations men — seeing her name splashed across international tabloids had taken a toll.
In explaining her decision to friends, Ms. Hicks, a communications director who rarely spoke publicly, made clear that she had no interest in being at the center of the public conversation.
That aversion to the spotlight had become increasingly difficult to maintain.
Ms. Hicks’s role in helping write a statement by Donald J. Trump Jr. about a 2016 meeting with Russian officials has drawn attention from federal investigators. On Tuesday, she testified for eight hours before the House Intelligence Committee and made headlines for admitting that she had sometimes told fibs as part of her job.
Last month, the man she had been dating, the former White House staff secretary Rob Porter, was accused by his former wives of domestic abuse, sparking an ongoing scandal that offered a glimpse of her closely guarded personal life and drew paparazzi to her apartment building. There were rumblings that Mr. Trump questioned Ms. Hicks’s judgment after the White House initially defended Mr. Porter, although a bevy of administration officials, including Ivanka Trump, later vouched for Ms. Hicks in on-the-record interviews.
Ms. Hicks had stopped monitoring news coverage of herself, restricting her television intake to Fox News, which she often watched on mute, assuming that the Trump-friendly network would rarely include her name on its chyrons.
Friends who reached out to her, offering support or guidance, acknowledged that Ms. Hicks has been distressed. But they also received text messages from her in which she declared that she was tougher than people assumed.
Ms. Hicks’s career followed a curious trajectory. As a young model, she appeared on the covers of young adult paperbacks and in Ralph Lauren catalogs before going to work for Ivanka Trump’s apparel and licensing brand. Even after she had begun serving as an Oval Office gatekeeper, she maintained a low public profile, which fueled the fascination — and sometimes disdain — of those who watch national politics closely.
Emily Nussbaum, the New Yorker’s television critic, often tweeted whimsically about Ms. Hicks, calling her an “It Girl.” (Ms. Hicks was once the face of a “Gossip Girl”-spinoff book series called “It Girl.”) Others dismissed her as a mere factotum, especially after a report that she was once tasked during the campaign with steaming Mr. Trump’s suits, sometimes while he was wearing them. On Wednesday, after news of Ms. Hicks’s exit was announced, the New Yorker writer Jia Tolentino tweeted: “Goodbye to Hope Hicks, an object lesson in the quickest way a woman can advance under misogyny: silence, beauty, and unconditional deference to men.”
In Washington, however, Ms. Hicks’s success was viewed as a product of other qualities, including her nuanced understanding of Mr. Trump’s moods, her ability to subtly nudge him away from his coarser impulses and her skill as a liaison for some of the most prominent journalists in the country.
“When she tells you something, you know she is speaking to the president, because she is with him all the time,” said Steve Scully, the senior executive producer at C-Span and coordinator of the network’s White House coverage. “It was amazing how often he would turn to Hope and ask her questions and ask her point of view. You can really tell, seeing the two of them interact, that there’s a trust between the two of them.”
Ms. Hicks was a key point of contact for reporters, editors and executives at television networks and major newspapers. Often, she could single-handedly arrange time with the easily distracted president. At a Paley Center panel discussion on Wednesday, the NBC News anchor Lester Holt described Ms. Hicks as his first contact for coordinating his interview with Mr. Trump last May. “She was quite helpful,” Mr. Holt said.
And in an administration riven by infighting, Ms. Hicks’s privileged position with the president meant that, for journalists, she was among the few officials whose information was deemed reliable, or at least not often compromised by personal squabbles.
Of course, she always advocated for her boss, lamenting that reporters did not see the empathetic and charming Mr. Trump whom she said she knew.
Ms. Hicks, a reluctant émigré to insular Washington, kept a tiny circle of confidants, complaining that she could not trust anyone in a company town. She frequently visited family in Connecticut and friends in New York, where she felt she could comfortably walk down the street without being accosted or asked for a favor.
She has told friends that, for now, she has no definite ideas for her life after the West Wing, except that she will not be living in Washington. An extended vacation with her family is planned. Book agents have come calling, but Ms. Hicks has told acquaintances that she is reluctant to write anything — although she has joked that a massive advance could change her mind.
“I think she would benefit from taking a minute or two to get some perspective on all of this,” said Michael Feldman, a Clinton White House veteran who is a family friend of Ms. Hicks.
“I don’t worry about Hope,” Mr. Feldman added, echoing other friends interviewed for this story. “I fully expect her to land on her feet.”
Those confident in Ms. Hicks’s future prospects sounded more concerned about Mr. Trump and his ability to work without an aide that he has relied on nearly every day for three years.
“This is not losing a staffer,” Mr. Feldman said. “This is like losing a limb.”