On Nov. 29, 2017, NBC revealed that a complaint of "inappropriate sexual behavior in the workplace" had been filed against the former Today anchor.
Four years later, the source says Abas, 52, is "very happy" in her relationship with Lauer, 63.
The couple met through work about 20 years ago and remained friends. Following Lauer's divorce from ex-wife Annette Roque in 2019, he and Abas began dating.
Lauer and Abas both live in New York and spend time with each other between her work travels, according to the source, who adds: "She is a dedicated businesswoman who loves to work. She is independent and has made a nice life for herself."
Jason Kempin/Getty; Jared Siskin/Patrick McMullan via Getty Matt Lauer, Shamin Abas
The Welsh-born publicist was previously married twice, first to a Detroit-based dentist and then to nightclub entrepreneur Frank Cilione.
As for Lauer, the source says Abas supports him "in every way" and that his past does not affect her business.
Almost two years after Lauer was fired, details of the complaint against the anchor were made public when Variety published an excerpt from Ronan Farrow's 2019 book, Catch and Kill: Lies, Spies, and a Conspiracy to Protect Predators, in which former NBC News employee Brooke Nevils alleged that Lauer anally raped her in his hotel room at the Sochi Olympics.
Nevils told Farrow that she was "too drunk to consent" and also stated multiple times that she did not want to have anal intercourse.
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splash news Shamin Abas, Matt Lauer
In the book, Nevils also said she had more sexual encounters with Lauer in New York City, telling Farrow: "It was completely transactional. It was not a relationship."
At the time, Lauer penned a lengthy letter in response, claiming the encounter was "extramarital, but consensual." He said the encounter in Sochi was the beginning of his affair with Nevils and "the first of many sexual encounters between us over the next several months."
Lauer additionally claimed that he has "never assaulted anyone or forced anyone to have sex. Period."
If you or someone you know has been sexually assaulted, please contact the National Sexual Assault Hotline at 1-800-656-HOPE (4673) or go to rainn.org.