The pair announced that they are separating this week after two years of marriage.
Aniston, 49, was reportedly annoyed when Theroux, 46, openly hugged Watts, 49, last year in New York allied to his partying in the Big Apple.
The pair were attending The Unveiling: Class by Taryn Toomey at Tribeca Studio with Watts last year when she was snapped sharing a warm hug with the 'Wanderlust' actor before having an intense chat with the Australian beauty.
The duo have been close friends for 16 years after starring together in the film 'Mulholland Drive' in 2001 but apparently Aniston was not impressed with their public display of affection.
The latest report comes as reports have surfaced that Aniston and Theroux might NOT have legally got married back in 2015.
Hollywood was left shell shocked after they released a statement this week announcing their separation.
RadarOnline.com reported how the couple have not spent a lot of time together in recent times and had been living separate lives.
Meanwhile, Aniston reportedly no longer like to live at their Greenwich Village apartment in New York after Theroux fell-out with one of his neighbors.
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