But before Aniston, came Heidi Bivens, a Hollywood costume designer and Theroux's girlfriend of 14 years.
Bivens has an impressive styling resume with films such as "The Wait," "Ceremony" and "Dedication," which Theroux directed. She has styled music videos for Kanye West, Cobra Starship and The White Stripes, as well as print ads for Coca-Cola, Hewlett-Packard and Target to name a few. She has experience in magazines including Vogue, GQ and In Style.
Sparks flew for Aniston and Theroux on the set of "Wanderlust" in the fall of 2010, when he was reportedly still living with Bivens. In March 2011, Bivens reportedly moved out of the New York City home she shared with Theroux.
"Heidi and Justin have been together for 14 years," Bivens rep confirmed to the New York Post in June 2011. "They met when she was 20 years old and he 24, and yes, she just moved out of their home last weekend. She has no comment."
Although the couple has not announced wedding plans just yet, the wedding may not be any time soon as Aniston is currently filming "We're The Millers," in which she stares as a prostitute. As for Theroux, he is reportedly working on the script for "Zoolander 2" so the couple will be very busy in the upcoming months. But there will no doubt be paparazzi hounding the pair to find out all the wedding details. And who knows, maybe they'll tie the knot before Aniston's ex Brad Pitt and Angelina Jolie.