TELLER COUNTY, Colo. (CBS4) – The key witness in the Patrick Frazee murder trial testified about her relationship with the defendant leading up to Kelsey Berreth‘s death. Krystal Lee took the stand Wednesday morning and sobbed as she told a chilling story to the court.

Krystal Lee Kenney

Krystal Lee Kenney (credit: CBS)

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She detailed for the court how she and Frazee rekindled their relationship about a year before Berreth was murdered. Holding back tears she detailed a long relationship with Frazee.

Lee said she then prepared divorce papers in order to be with Frazee.

Patrick Frazee (credit: CBS)

Lee had previously told investigators a horrific account of how she said Frazee told her he allegedly murdered the mother of his little girl.

Kelsey Berreth (credit: Woodland Park Police)

Lee said initially Frazee asked her to kill the 29-year-old mother on three occasions, including suggesting poisoning Berreth’s coffee. Lee said that she brought a poisoned Starbucks drink to Berreth but it wasn’t tainted.

Lee said Frazee claimed his daughter was being abused by Berreth.

(credit: CBS)

Lee said Frazee wanted her to kill Berreth using a pipe and then another time with a bat, but each time she backed out.

Lee testified that Thanksgiving night 2018 Frazee called her and said, “That I had a mess to clean up.”

Lee said Frazee told her he killed Berreth in her Woodland Park home by beating Berreth to death with a baseball bat. Prosecutors said that after Frazee allegedly killed Berreth he called his former girlfriend to help him clean up. Investigators said Lee admitted watching Frazee burn Berreth’s remains in a black tote outside his home.

“He wanted her (Kelsey) not to be a problem any more… he wanted her dead,” Lee testified.

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Lee also detailed in a tear-filled account of how she became pregnant and Frazee asked her if she “was a baby killer or not.” Lee testified that she terminated that pregnancy.

Krystal Lee Kenney

Krystal Lee Kenney (credit: CBS)

Lee then drove back to Idaho where she lived. Along the way, she said she sent text messages to Berreth’s mother and employer from Berreth’s phone. She claimed Frazee had directed her to do this to lead people to believe that Berreth was still alive.

The investigation of Berreth’s disappearance led the FBI to contact Krystal Lee who was at a rodeo in Las Vegas. Lee acknowledged lying to the FBI at first, but then got a lawyer and was able to cut a plea deal for a three-year maximum sentence in return for her testimony.

She pleaded guilty earlier to tampering with evidence by transporting Berreth’s cell phone.

Jury selection and opening statements in the trial wrapped up last week. Testimony began on Monday with Berreth’s family, her mother and brother, testifying.

On Tuesday, Frazee’s brother, Sean Frazee, testified that the defendant showed up two hours after the family ate Thanksgiving dinner on Nov. 22, 2018 — the last day Berreth was seen alive.

Sean, who said he has “not been close” with his brother, said dinner began at 3 p.m. at their mother’s house but Patrick did not arrive until 5 p.m. Sean said that day was the first time he’d met his niece, Kaylee, who was about a year old at the time.

Kelsey Berreth and Patrick Frazee

Kelsey Berreth and Patrick Frazee (credit: Facebook/Missing Mother – Kelsey Berreth)

During testimony on Monday, details were released that Berreth, Patrick Frazee and their daughter were seen on video entering Berrreth’s home in Woodland Park at 1:24 p.m. on Thanksgiving. Three hours later, security cameras showed Patrick Frazee leaving with their daughter, but Berreth was never seen coming out. However, Chad Mininger, a DA investigators for El Paso County said there were issues with the system not always capturing and storing video.

A neighbor’s surveillance camera captured 11 images of Patrick Frazee that day.

Frazee has entered a not guilty plea to charges of first-degree murder, solicitation to commit murder and tampering with a body. He faces life in prison if convicted.

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Next attorneys for Frazee will cross examine Krystal Lee attempting to discredit her story.