When the skies finally opened up on Friday and rain began to fall over the US Capitol, Clinton's turn to stand before the thousands gathered on the Mall and take the oath of office as the 45th president never came.

Instead, she remained seated with her husband, Bill Clinton, by her side. And she watched a man whom she believes is fundamentally unfit to hold the highest office of the land get sworn in as her next president.

Donald Trump's inauguration on Friday and the ceremonial passing of the baton by Barack Obama crystalized before a watchful nation the deeply personal loss that Clinton had suffered in November.

For the former Democratic presidential nominee, the decision to attend Friday's ceremony was not an easy one.

Clinton anticipated that it would be painful for her to watch Trump become the next president, according to a former aide, but felt she had no choice but to attend given her role both as former first lady and Trump's challenger. It weighed on her, this aide added, that her presence symbolized the peaceful transition of power, regardless of her own emotions about the day.

The Clintons arrived on Capitol Hill shortly before the swearing-in. At the same time, the presidential motorcade was making its way down Pennsylvania Ave. towards the Capitol. In one car sat two men who had each taken away Clinton's dreams of becoming president -- Obama and Trump.

Clinton wore a white coat -- something she did often on the campaign trail to represent the color women wore during the suffrage movement. She and Bill Clinton were introduced to the inaugural stage by the announcer as "the 42nd president of the United States, William Jefferson Clinton, and the honorable Hillary Rodham Clinton."

For Clinton's supporters, both were painful reminders of how close Clinton -- the first woman to clinch a major political party's nomination for president -- had come to becoming to the president of the United States.

With the exception of when she exchanged pleasantries with other dignitaries on the stage, Clinton, for the most part, appeared stoic.

Trump, with his former political opponent seated behind him, delivered an inaugural address reminiscent of his campaign speeches, vowing that the "forgotten men and women of our country will be forgotten no longer."

"This American carnage stops right here and stops right now," Trump said.

Trump did not mention Clinton in the address.

But during the luncheon honoring Trump and Vice President Mike Pence in the Capitol's Statuary Hall, Trump rose to deliver gracious remarks about Clinton. It was a striking contrast from even a few months ago, when Trump had threatened to jail her if he became president and repeatedly dredged up some of the most painful moments of the Clintons' turbulent marriage, including Bill Clinton's infidelities.

"I was very honored, very, very honored, when I heard that President Bill Clinton and Secretary Hilary Clinton was coming today," Trump said, before asking both to stand, when they received a long round of applause.

"Honestly," Trump added, "there's nothing more I can say because I have a lot of respect for those two people."

For Clinton and her aides, losing the presidential election to Trump had been a difficult scenario to imagine for the better part of the general election. In the heat of a contentious and bitter campaign, the former secretary of state let her tone grow increasingly dark, as she repeatedly warned the American people that the values Trump espoused were un-American.

"Imagine that on January 20, 2017, it is Donald Trump standing in front of our Capitol and taking the oath of office," Clinton told her supporters in Las Vegas, Nevada, just three days out from the election. "Imagine with me what it would be like to have Donald Trump sitting in the Oval Office come next January."

More than two months after the election, a political scandal that had haunted Clinton's presidential run still lingered.

GOP Rep. Jason Chaffetz, the chairman of the House Oversight Committee that investigated Clinton's use of a private email service during her time at the State Department, posted a photo of himself shaking hands with Clinton on the inaugural platform.

So pleased she is not the President. I thanked her for her service and wished her luck. The investigation continues. A photo posted by Jason Chaffetz (@jasoninthehouse) on Jan 20, 2017 at 12:31pm PST

His caption read: "So pleased she is not the President. I thanked her for her service and wished her luck. The investigation continues."

Republican Sen. John Cornyn, who was seated at the same table as Clinton for the lunch, told CNN that she appeared to be in good spirits but lamented the vitriolic nature of politics.

"She did talk about how she hoped our politics was more consensus-building and everybody can have their views but it doesn't have to be poisonous," Cornyn said.