Ex-Girlfriend of Church Gunman Fights Tears as She Recalls Troubled Relationship: 'Devin Was a Monster'

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A young woman says she knows the killer behind the Texas church massacre better than just about anyone else after dating the man she calls a "disgusting person" for three years.

Read: Hero in Church Massacre Says He Was 'Scared To Death' While Pursuing Shooter

Brittany Adcock, 22, was just 13 years old when she started dated Devin Kelley. She says he took her virginity while she was still in middle school. 

“He was a pervert," she told Inside Edition. "A pedophile.” 

It's still hard for her to talk about dating Kelley without crying. She told Inside Edition that he continued to stalk her for years, even after he was married, threatening to post nude photos of her on social media.

“He's a very disgusting person," she said. "He really is.” 

When he married his second wife, Danielle, she says Kelley made Adcock a bizarre offer.

“He said... 'Come live with me and my wife. I'll take care of you so long as you be topless, you walk around topless all the time,'” she claimed. 

Her last contact with the gunman was just six months ago. 

Read: Video From Texas Church Shows Mom Who Died While Shielding Her Kids From Gunfire Week Before Shooting

“I always hoped that he had finally given up," she said. "I always thought, 'It has been so many years since we've broken up — why are you still contacting me?' The last time he contacted me I said exactly that."

Meanwhile, newly released video shows the moment the gunman was cornered. 

It was shot by hero John Langendorff who gave chase until Kelley lost control of his white SUV and crashed. Kelley took his own life in the process. 

In the video, sharpshooters were at the ready as cops open the door to find Kelley dead from a self-inflicted gunshot wound.