The black and white text of the 11-year-old emails did little to betray their explosive contents.
But the sender's anguish over the recipient's alleged affair with her husband helped end the lengthy career of Goldman Sachs' top female executive - and heaped personal humiliation on her to boot.
Retired NBC News executive Cheryl Gould, 73, confronted Goldman Sachs now-former Chief Legal Officer and General Counsel Kathryn Ruemmler, 54, for sleeping with her husband Reid Weingarten, 75.
But a source close to the situation has now claimed that Ruemmler, a former White House counsel to Barack Obama, was also a victim of Weingarten's lies and deception.
'Kathy didn't know about Cheryl's existence. Reid didn't mention her,' the source told the Daily Mail after Ruemmler resigned from Goldman Sachs on Thursday.
She believed they were in a 'genuine relationship,' the insider said.
Gould, who was the first female executive producer of NBC's Nightly News, criticized Ruemmler over what she claimed was her husband's 'addiction' to his mistress.
She appeared to blame Ruemmler for Weingarten's infidelity, ordered her to 'stay away' from him and suggested the affair was a betrayal of sisterhood.
Kathryn Ruemmler, seen in 2013, 'regretfully' stepped down from her role as Goldman's Chief Legal Officer and General Counsel on Thursday morning. Her resignation is effective June 30
Ruemmler recently faced major backlash over her yearslong relationship with Reid Weingarten (seen in 2013), which saw him be unfaithful to his now-wife Cheryl Gould
She wrote: 'I hope now=you can find true happiness without having a relationship with someone else[‘]s husband.'
The Daily Mail's source insists Ruemmler believed Weingarten to be a single man and suggested Gould's email was unacceptable.
Ruemmler and Weingarten, a top criminal defense lawyer who was one of Epstein's personal attorneys, began dating while she was living in Washington, DC.
Weingarten was also residing in the capital.
'Reid had an apartment in DC, but there were no pictures of Cheryl,' the insider claimed, suggesting Ruemmler had no reason to believe he was with anyone else.
Ruemmler was 'devastated when she found out about Cheryl,' our source said.
The insider also noted that the relationship had ended prior to the start of Weingarten and Gould's marriage.
Although it's unclear exactly when Weingarten and Gould got married, reports dating back to as early as 2005 have referred to them as a couple.
But a source close to the situation told the Daily Mail that Ruemmler was misled by Weingarten and did not know about his relationship with Cheryl Gould (pictured)
Gould sent an initial email to Ruemmler on June 13, 2015, ordering her to 'stay away' from Weingarten
Two days later, the NBC executive sent another message condemning the affair and doubling down on her claim that the couple were through
Ruemmler, who appears to have forwarded Gould's email on to Jeffrey Epstein, claimed she found it 'dispositive' that Weingarten 'would permit this message to stand'
They are parents to a son, with Gould saying in her email to Ruemmler how her child had been distraught by his father's infidelity.
The correspondence became part of the Epstein files when Ruemmler - who was a close associate of the late pedophile - forwarded the email to him a day after it was sent in June 2015 to express her shock.
'I have reread this 10 times. The fact he would permit this message to stand is dispositive,' Ruemmler wrote, referring to Weingarten.
When asked why Ruemmler forwarded Gould's email on to Epstein, the insider said that Weingarten had already dragged their private life into the narrative.
'Reid had mentioned their relationship to Epstein,' the source said.
Ruemmler was shocked by the message and did not understand 'how he could let this stand when it was so far removed from reality and the truth,' according to the source.
'Kathy was not close with Epstein. She had a yearslong relationship after [she and Weingarten broke up] that she did not tell Epstein about,' the insider added.
The source claimed Ruemmler would never have told Epstein about the relationship with Weingarten, had he not already disclosed it.
Jeffrey Epstein, left, and attorney Reid Weingarten, second from right, listen as attorney Martin Weinberg, right, speaks during a July 2019 bail hearing in federal court in NYC
Kathryn Ruemmler (left) served as Barack Obama's (third-right) top White House lawyer. They are seen with Treasury Secretary Jack Lew, Joe Biden, Sylvia Mathews Burwell and Alyssa Mastromonaco during an October 2013 meeting
Ruemmler is believed to have befriended Epstein around the time she left the Obama administration in 2014.
He had been convicted for soliciting prostitution from a minor six years earlier and was on the sex offenders' register.
Ruemmler's name was mentioned in more than 10,000 documents released by the Department of Justice from the Epstein Files.
She called him 'Uncle Jeffrey' in emails, wrote that she 'adored him,' called him 'sweetie,' signed emails 'xoxo,' branded him 'wonderful Jeffrey' and even likened him to a sibling.
Epstein showered Ruemmler with gifts including a Hermes purse, $10,000 in Bergdorf Goodman gift cards and a $50,000 private jet flight.
Ruemmler says she turned down the latter.
Defending herself after their links first emerged, Ruemmler said she was seeking to develop and maintain a professional association with him.
Ruemmler has repeatedly tried to distance herself from Jeffrey Esptein, seen in 2005, and called him a 'monster' in recent statements
Goldman CEO David Solomon, pictured last year, has accepted Ruemmler's resignation and in a statement to the Daily Mail called her an 'extraordinary general counsel'
Announcing her resignation, Ruemmler said: 'Since I joined Goldman Sachs six years ago, it has been my privilege to help oversee the firm's legal, reputational, and regulatory matters; to enhance our strong risk management processes; and to ensure that we live by our core value of integrity in everything we do.
'My responsibility is to put Goldman Sachs' interests first.'
The bank's CEO David Solomon added: 'As one of the most accomplished professionals in her field, Kathy has also been a mentor and friend to many of our people, and she will be missed. I accepted her resignation, and I respect her decision.'
The Daily Mail has contacted Gould and Weingarten for comment.