After all of the Uncool Bermuda Triangle messiness between Brad Pitt, Angelina Jolie and Jennifer Aniston, you would have thought that Jennifer Aniston would never, ever go for a guy in a long-term relationship, right? Wrong. When Jennifer worked with Justin Theroux in 2010, he had a long-term, live-in girlfriend named Heidi Bivens. It was widely believed that Justin and Jenner had an affair in 2010, then started seeing more of each other in the spring of 2011. The “are they or aren’t they dating?” thing went on for a few months until suddenly Justin and Jennifer were “official” and Heidi suddenly moved out of the apartment she had shared with Justin for a decade. We know about the timeline because Heidi’s mother spoke to the press several times in 2011, and Heidi’s mom also basically said that Jennifer and Heidi met face-to-face after Jennifer had “homewrecked” Heidi and Justin’s relationship. Well, Heidi’s mom is still talking about how Justin left Heidi devastated.

Justin Theroux‘s long-term lover is still heartbroken from their split five years after he dumped her for Jennifer Aniston, RadarOnline.com can exclusively reveal. Costume designer Heidi Bivens, 40, who dated The Leftovers star for 14 years, has been unable to move on and find a new boyfriend since the brutal breakup, her mother Marilyn said in a shocking tell-all interview. Marilyn, 71, also revealed coldhearted Theroux lied to her daughter about his and Aniston’s budding romance after the star couple first met. Marilyn, who lives in Annandale, Virginia, once considered Theroux, 44, her son after welcoming him into their family for 14 years — until he betrayed them for a romance with the 47-year-old Friends actress.

“My baby’s heart was pierced. It was a terrible time,” Marilyn, holding back tears, told Radar after reciting a prayer. “Heidi told me what Justin had told her, that something was going to be written about him and Jennifer, that something was going on between them and he wanted her to know that it was nothing, there was nothing to it. Out of his own mouth he told my daughter there was nothing to [the news he was involved with Jennifer].”

After word Theroux and Aniston’s relationship was confirmed, Heidi spoke to her mom on the phone to break the bad news.

“And my sweet Heidi she calls me and says, ‘Oh mommy,’” said Marilyn. “I was going through cancer at the time. It was a time that hurt our family.”

Marilyn said Theroux developed a “dark and sinister” side as his acting career took off by constantly “changing faces” and struggled to separate his life from the characters he would play.

“Being an actor and the parts that you choose to play, you become those characters,” noted Marilyn. “You have to enter into everything they are to actually become. I remember once Heidi was speaking about one of his parts, she told him he played it so well and he told her, ‘I was that character.’ And I thought when you’re in that path and continue to change faces and patterns, you become the dark and sinister characters. There are children of light and children of darkness. His world was very dark.” And so is Jennifer’s, insisted the mom. “We have a choice, even if you’re not a Christian you know what’s good; you know the choice of darkness and the people who are acting out that darkness. Justin is married now to Jennifer. They are, I believe, alike in spirit. They complement one another the spirit of the world brought them together.”

Asked if Bivens will ever overcome her heartbreak and find love again, Marilyn wasn’t so confident.

“Heidi’s wound is closed but there’s still a scar and we’re praying for a Godly man to come and find her because she’s ready,” said Marilyn. Despite Theroux blindsiding her daughter, Marilyn refused to condemn the actor for his betrayal.

“It would be opening up a grave and exhuming the body. They were together 14 years. I would go and visit, he would visit with Heidi at Thanksgiving and Christmas. I forgive him,” she said of the star, who never reached out again to the family or Bivens after the split.

[From Radar]

God, I do feel sorry for Heidi even after all of these years. She always handled the breakup with class though – she never did a tell-all interview, and I sort of suspected that Aniston’s people might have cut Heidi a check in exchange for an NDA (too bad Aniston didn’t get Heidi’s mom to sign one, eh?). Heidi was with Justin for 14 YEARS. She was with him from the age of 20 to 34. They had built a home together. And she had to move out of that home after he (allegedly) cheated on her and lied to her. Just remember that the next time everyone’s like “oh, poor Jennifer Aniston.” Nope. JustJen is THE DARKNESS.

Photos courtesy of WENN and Brian Flannery/Flynetpictures.com.