Aniston was spotted out at Soho House in Los Angeles on Tuesday with her former Friends co-star Courteney Cox, Tobey Maguire's wife Jennifer Meyer, and her hairstylist, Chris McMillan.
"It was all her friends," a source said, adding it was "mellow fun dinner."
Although Theroux, currently in New York shooting his new HBO series The Leftovers, is far away, Aniston is keeping him close. She was spotted wearing a "T" necklace for her interview with feminist icon Gloria Steinem over the weekend.
Theroux, who has been spotted partying with Orlando Bloom and attending the Manhattan opening party of the Deth Killers pop-up store in Bushwick, has also been mourning the loss of his friend, Philip Seymour Hoffman. The actor paid a visit to Hoffman's partner, Mimi O'Donnell, on February 3 and attended Hoffman's funeral on February 7.