WASHINGTON — A year ago, few “on the outside” — a phrase perhaps tellingly favored in the Trump White House — would have guessed that Kellyanne Conway would be the one hanging on as other high-profile aides pull their rip cords.

A year ago, Ms. Conway, the president’s counselor, told Americans of the fictional “Bowling Green massacre,” drawing ridicule from cable TV hosts and liberal critics. She declared that the White House was merely presenting “alternative facts” when it described an inauguration crowd in superlatives that did not comport with reality. She was painted into an unhinged “Saturday Night Live” caricature. For a pollster with a long history of working well with the news media, the attacks were jarring, according to her allies.

But in this White House, a lot can change in a year.

More than a dozen high-profile departures later — and amid tumult, scandal and an ever-unfolding investigation into the Trump campaign’s ties to Russia — Ms. Conway, 51, is one of the few remaining prominent aides from the campaign. In a White House with the highest turnover rates in decades, she has survived by knowing when to step back from the spotlight, keeping the president’s ear, focusing on a policy issue significant to the poor and working class, and maintaining an unflinching loyalty to President Trump even as she outmaneuvers rivals on the staff.

The public criticism hasn’t abated, but Ms. Conway’s skin is thicker than it used to be.

“I don’t respond to or read 99 percent of it,” Ms. Conway said in a brief interview on Saturday, “because it is so reflexive and unthoughtful.”