Amber Frey’s testimony helped send her cheating lover, double murderer Scott Peterson, to death row – but her father tells The ENQUIRER he thinks she still carries a torch for the killer!

Even more tragic, the nightmare not only destroyed Amber’s life, it nearly pushed her over the edge mentally, he said.

In a world exclusive interview, Ron Frey, 62, opened up to The ENQUIRER about his daughter’s struggles, and his hope is that Peterson will one day confess to the slayings. “The ordeal flipped my daughter’s brain upside down and scarred her for life,” he said. “Amber is mentally unstable for it. That’s just too much on anyone” Peterson’s pregnant wife, Laci, went missing on Christmas Eve 2002. Soon after, single mom Amber – then a massage therapist in Fresno –revealed she’d been having an affair with Peterson.

In 2005, Peterson was sentenced to death for the murders of Laci and their unborn son. Amber went on to have a son with another man, and got married in 2006, but was divorced two years later.

But after her romance with Peterson, Amber “was never right,” her father said. “She just hasn’t been able to maintain a relationship since then.

“Some people fall in love and never forget it. She’s far from regular. I just don’t know how to explain it. “There have been two or three guys who’ve been really attractive and successful. ButScott broke her heart, and it’s never been able to be repaired.”

Ron claimed his daughter remains irreparably damaged. “Amber is so out there that it’s a nightmare,” he said.

While Peterson has been on death row since 2005, Ron says he doesn’t want to see the now 42-year-old creep put to death. “I’d prefer not to have him executed if he just admitted it,” Ron told The ENQUIRER. “I wish he’d tell what he did and get it over with.”Amber, 39, is raising daughter Ayiana, 13, and son Justin, 10,two children on her own. She wrote a best-selling book about her ordeal, “Witness: For the Prosecution of Scott Peterson,” but lost her home to foreclosure in 2008.

Amber’s attorney, Gloria Allred, said in a statement to The ENQUIRER: “She does not carry a torch for Scott Peterson. She does not need and is not seeking mental health services because of him. She works and takes care of her children. She is feeling very positive about her future.”

But she has no doubt that testifying against Peterson was the right thing to do.

But in a 2006 interview, Amber said: “The whole experience was very trying, emotionally. For most people, it was just a story – but to me, it was part of my life, a very painful part.”