Jennifer Aniston is said to be highly upset after learning that Emma Stone had allegedly been caught flirting with her estranged husband, Justin Theroux.

According to a new report, it all went down after Theroux traveled to Paris after his split from Aniston last month and began spending time with the much younger actress as he took in the sights of the French city.

“Jen’s been keeping a low-profile after the split, so of course it was frustrating to see Justin hanging out at Paris Fashion Week with beautiful women like Emma,” an insider revealed to Radar Online on March 28.

When Did Justin Theroux And Emma Stone's Relationship Begin?

Theroux and Stone reportedly became close during the time they were working together on the television series Maniac, and Stone has reportedly been in contact with Aniston as well. As the outlet explained, the two actresses have met with each other a few times and have always gotten along well during their encounters.

“So this is a tough pill to swallow, to say the least,” the source continued. “Jen knows that Justin is going to move on eventually, but she is crushed over the rumors.”

Jennifer Aniston And Justin Theroux Split Just Over One Month Ago

Following just two years of marriage, Aniston and Theroux announced they were parting ways on Feb. 15. The couple had initially tied the knot in August 2015 at their home in Bel Air, California, after striking up a romance on the set of Wanderlust.

According to the couple's statement, their decision to end their marriage was mutual.

In the weeks since their breakup, Aniston has been keeping to herself but was spotted spending time with several of her girlfriends, including Courteney Cox, whom she starred alongside in Friends.

Justin Theroux Has Already Been Linked To Other Women

Weeks ago, rumors began swirling in regard to a possible romance between Theroux and artist Petra Collins. He's also been linked to Olivia Munn in the weeks since his split from Aniston, but as fans well know, Munn and Aniston are quite close, and it seems highly unlikely that Munn would ever betray her in such a way.

As for Aniston, she's been facing rumors of a possible reunion with her first husband, Brad Pitt. That said, those rumors have been shut down on numerous occasions.