Once the President's closest West Wing confidante -- the recipient of his repeated phone calls, the witness to his angriest moments, and according to other campaign aides, the person who steamed wrinkles out of his pants -- sources now say their relationship has changed. Instead of carrying out a near-constant conversation, they rarely speak.

Hicks returned to Washington on Wednesday to testify behind closed doors before the House Judiciary Committee for its investigation into possible obstruction of justice by the President. This account is based on interviews with several current and former administration officials, as well as people close to Trump and Hicks.

The once-close pair's communication first slowed, then came to a virtual halt, after she left the White House. She told those around her that it wasn't a representation of her feelings toward the man she worked for, but a desire to distance herself from the orbit she had occupied for so long: his. There were several times when she didn't return Trump's call. According to two people familiar with his remark, Trump asked on multiple occasions, "What happened to Hope?"

People close to Hicks say that, despite her distance, she remains on the President's side. She has kept in close contact with White House and Trump campaign officials, who send her updates from the West Wing and the trail or call for advice on dealing with the mercurial President she built a close relationship with.

But Hicks returned to a different Washington Wednesday than the one she occupied more than a year ago. Democrats now control the House, and have launched an onslaught of investigations into the president and his administration. Now they will have one of the President's most trusted advisers on their turf. In their first interview with a former White House official since Trump vowed to "fight all the subpoenas," Democrats wanted to probe Hicks on everything from James Comey's firing to Trump's demands that then-Attorney General Jeff Sessions un-recuse himself.

Hicks joins a long list of current and former Trump aides called to appear before lawmakers intent on probing Trump's attempts to short-circuit the investigation led by former special counsel Robert Mueller. While some of those staffers were privy to key moments and critical decisions over the course of Trump's campaign and presidency, perhaps no other staffer has the potential to offer Democrats as much insight into Trump's thinking and mindset than Hicks.

Trump continued his defense of the "wonderful Hope Hicks" Wednesday, tweeting that the hearing was "very unfair and costly to her."

An original who left the fold

A onetime model and public relations professional, Hicks joined Trump's presidential campaign early and remained one of the few aides to follow him from his political beginnings to the White House. She maintained a close relationship not just with the President -- who called her "Hopey" -- but with members of his family, including Ivanka Trump and Jared Kushner, both senior advisers.

She carried out that role barely uttering a single word in public -- no television interviews and only a few scattered appearances at microphones alongside Trump.

Hicks stepped down from her role as White House communications director and left the administration last March. She moved out of her luxe Washington apartment and relocated to Manhattan, where she kept a low profile for the next several months and kept in touch with her former White House colleagues.

At times, she contemplated returning to the administration, quizzing friends last summer about what position she could have if she made a comeback. She was even spotted boarding Air Force One last August ahead of the President's campaign rally in Ohio -- a spur-of-the-moment return to presidential travel after visiting with her former colleagues at Trump's New Jersey golf club.

But mostly, people who spoke to Hicks said she was trying to adjust after three years in Trump's orbit, a whirlwind that saw both her and the President go from political novices to running the country.

Seven months after her departure, the Fox corporation announced it had hired Hicks to become the company's chief communications officer, where she would be based in Los Angeles. Since moving to the West Coast, Hicks, a Connecticut native, has been spotted in upscale restaurants, at yoga studios, and -- based on those who know her -- living a relatively unassuming life, aware that she carries the echo of a polarizing president.

But several sources with knowledge of their relationship said one aspect of her new life is unexpected: Hicks rarely speaks to the President anymore.

A witness to all

People who know the President best say he is an avid caller. He will phone lawmakers, old friends and his staff multiple times a day to quiz them on everything from which Democratic presidential candidates are ahead or to complain about a recent segment he saw on cable news.

But when she worked for him, Trump's call log with Hicks was exorbitant, people close to both of them said. He regularly phoned her more than he did his chief of staff, regardless of who was occupying that title at the time. She rarely left White House grounds during the day because she needed to be within earshot of Trump, who often summoned her at a moment's notice. And if it wasn't Trump on the other end of the phone, it was often another White House staffer or outside adviser inquiring about the President's mood and asking advice on how best to broach an issue with him.

In her tenure as Trump's communications guru, Hicks witnessed some of darkest moments of his presidency. She described in interviews with Mueller's investigators a seething President after the special counsel's appointment, saying she'd only seen him angrier after the "Access Hollywood" tape that captured him boasting about grabbing women was released.

She also described the President being upset that too many people were aware of emails related to a now-infamous meeting at Trump Tower with Russian officials linked to the Kremlin. In a text message exchange with Trump's eldest son, Donald Trump Jr., Hicks detailed her attempts to advise the President on a communications strategy surrounding the meeting.

"I think that's right, too, but boss man worried it invites a lot of questions," she wrote when Donald Trump Jr. suggested an edit to a prepared statement.

The White House asserted immunity to prevent Hicks from testifying Wednesday about her time at the White House, setting up a potential showdown with Democrats when she appeared behind closed doors.

But Democrats' on the House Judiciary Committee also planned to press Hicks on events that occurred before Trump took office, including her knowledge of the hush-money scheme to silence Trump's extramarital affairs in the run-up to the 2016 presidential election, a committee aide told CNN.