She is "the other woman" in the Laci Peterson tragedy: Amber Frey, whispy-blonde mistress to convicted killer Scott Peterson -- the star witness who helped bring Peterson to justice for killing his wife and unborn son. "Extra's" Tanika Ray went on the record with Amber to uncover how she felt about her part in the most-watched and talked-about trial of 2004.

"I was scared. I was a very scared woman that had no idea what was going on," Amber told Tanika.

So did she love Scott? "Those emotions are very complicated," Amber admitted.

And what was the first thing that attracted her to him? "He was just very charming, very comfortable to be around," Amber said, but nonetheless, "The only word that describes him is sociopath."

Amber played a key role in building the case against Peterson when she agreed to help police gather evidence by taping her phone conversations with Scott. "I'd question him and then he just had a way of manipulating the conversation," she remembered.

Now promoting her instant best seller, "Witness for the Prosecution of Scott Peterson," 29-year-old, single mom and message therapist Amber revealed a regret about her relationship with the killer cad: "Being with him on the first date." Even though she admits to having had a little alcohol, she maintained, "It's not an excuse."

As she makes the media rounds, Amber keeps attorney Gloria Allred by her side, and even holds her hand when the questions get personal. Allred told Tanika there's such demand for Amber's side of the story that CBS just purchased the rights to turn her book into a TV movie - though Amber has given no thought to who she'd want to play her in it.

Meanwhile, Amber agreed to get grilled by some "Extra" viewers, answering questions sent in from our audience:

Question 1: Why did you write this book and why are you capitalizing on such a terrible tragedy? "I will agree it was a tragedy," Amber responded. "I want people to understand that I have lost a lot of work and income by my assistance with law enforcement, and I owe it to my children to secure their future."

Question 2: Do you think Scott deserves the death penalty? Answered Amber, "My question is, did Laci and Connor deserve to die?"

As Peterson awaits his formal sentencing next month, his ex-lover states she won't go to jail and visit him, declaring she's done: "I have closure."