The former wife of Gilgo Beach serial killer Rex Heuermann still lives in the same house where he murdered seven women — and even sleeps in the “kill room,” constantly reliving the victims’ horrific final moments, she told the makers of a Peacock documentary series.

In the final episode of “The Gilgo Beach Killer: House of Secrets” — which airs Thursday — Asa Ellerup revealed she’s redone their Long Island basement where she said he told her he methodically murdered and dismembered victims before dumping their remains along a nearby beach.

The documentary's makers showed Ellerup walking down the Massapequa Park basement's stairs as words on the screen inform viewers that she had been sleeping there for about a month prior to Heuermann pleading guilty to the murders April 8.

“This whole basement looks very different, it’s been completely gutted and redone, new floor, new walls, new moldings, new doors,” Ellerup said in episode four of the series. (Peacock is owned by NBCUniversal, the parent company of NBC News.)

Then an off-camera voice asked Ellerup: “What do you want people to know (about) why you moved into the basement, into the kill room, into the room where these heinous things happened?”

“The brutal truth is that Rex Heuermann said he dismembered the bodies in this room. That is the brutal truth, OK?” Ellerup said.

“Now there’s me, I’m in this room and I’m here because I do feel spiritual. I am trying to say spiritually, in my own way, that I am really sorry for what these victims went through.”

Ellerup said the horrors of Heuermann’s reign of terror continue to dominate her waking and sleeping hours.

“I am haunted by dreams every night,” she said. “It will never go away. It will follow me for the rest of my life.”

Heuermann has admitted to killing eight women whose remains were found along Long Island’s Gilgo Beach.

As a condition of pleading guilty, he was allowed to meet one-on-one with his former wife and their daughter, Victoria Heuermann, to confess to them first before doing it in court. The pair divorced after he was arrested in July 2023.

The women said in the documentary that they pressed the killer to explain his motives but he didn’t explicitly spell out what pushed him to commit these unspeakable acts.

“He said that his demons got to him,” Victoria Heuermann said.

She said that she asked her father if he ever stopped to consider that his victims were someone’s beloved family member and that he responded that the women he killed weren’t really people in his mind.

“I’m like, well, did you see them as somebody’s daughter?” Victoria Heuermann said she asked. “He told me he didn’t even see them as human.”

Heuermann maintained a strict barrier between his victims and his family.

“They were completely kept in separate worlds (to Huermann) and he never let the two cross,” Victoria Heuermann said.

“So I’m like, OK, he’s a loving dad and a serial killer: How did he manage that the two never crossed? Seven women have been murdered in this house. It’s hard to stomach,” she said.

The hulking, 6-foot-4, 250-pound Heuermann targeted sex workers who were no taller than 5-foot-5, authorities said.

Heuermann has admitted to killing Melissa Barthelemy, 24, Megan Waterman, 22, Amber Lynn Costello, 27, Maureen Brainard-Barnes, 25, Jessica Taylor, 20, Sandra Costilla, 28, Valerie Mack, 24, and Karen Vergata, 34,

Only one of the women, whom he killed in his car, was a spontaneous slaying, Heuermann said. The rest of the killings were all planned, the victims slain inside the family’s home, most in the basement, when the rest of the family was not home, Heuermann said.

He’s set to be sentenced to life without the possibility of parole June 17.

Heuermann’s defense lawyer could not be immediately reached for comment Wednesday.