The actress celebrated her 49th birthday on Feb. 11, just days before announcing the split, at her close friend and former Friends costar Courteney Cox‘s house, a source tells PEOPLE. “They had friends over, hung out and also celebrated her special day,” says the source. “Spending time at Courteney’s always make her happy.”
“Her close friends knew about the split for several weeks before the announcement,” says the source.
“She has a huge group of girlfriends who make sure she isn’t alone,” the source adds. “Jen truly has the best friends. They are real friends that she has had for many years. They always support each other.”
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The source says that Aniston “is a great friend, who likes to organize fun get-togethers and host people,” and now that she needs the support, “her friends take care of her.”
The actress has also been spending time with celebrity yoga instructor Mandy Ingber. “This might not be the happiest time for Jen, but she still tries to stay happy,” says the source. “For her, working out is very important. It helps her stay focused and happier. She works out most days.”
And days after announcing the split, Aniston was spotted out at the Los Angeles premiere of Game Night, to support her longtime friend Jason Bateman.
On Feb. 15, Aniston and Theroux announced that they had split after two and a half years of marriage — and seven years as a couple.
“In an effort to reduce any further speculation, we have decided to announce our separation,” the former couple said in a joint statement. “This decision was mutual and lovingly made at the end of last year. We are two best friends who have decided to part ways as a couple, but look forward to continuing our cherished friendship.”
While the couple announced that they split at the end of last year, they celebrated the New Year together with their annual vacation to Cabo San Lucas, Mexico, alongside a handful of close pals including Jason Bateman and his family.
Aniston and Theroux began dating in 2011. They later married in a surprise and secret ceremony on August 5, 2015 — just a few days before Theroux’s 44th birthday.