PHOENIX (AZFamily) — New details have been uncovered about the murder of 25-year-old Doris Aguilar, who was found dead in a car next to Juan Cuellar, the man her family said stalked her.

After getting Aguilar’s medical examiner report, Arizona’s Family learned exactly what was written inside the most crucial piece of evidence: Cuellar’s notebook. But police say the truth is mixed with many lies.

On July 7, two bodies were found in a car outside a west Phoenix Longhorn Steakhouse. Eventually, they identified them as Aguilar, who was shot in the head, and Juan Cuellar, lying next to her in the driver’s seat. Phoenix Police said he took his own life after killing Aguilar.

Inside that car with them – a notebook.

“It took a little bit to get through the notebook, which offers a whole different dynamic of what happened than maybe what some of the evidence showed,” said Phoenix Police Sergeant Rob Scherer.

Aguilar, an avid gym goer, had gone missing in Phoenix on July 1. Her family launched a search for her with a private investigator. During the investigation, they feared Cuellar was the reason for her disappearance.

His involvement and responsibility for her death proved to be true, according to the police.

In the notebook found in the car with them, Cuellar wrote this:

“She picked it up. She didn’t know that the safety was off. I went to grab the gun, and it went off. I panicked and left. I knew it was going to be my fault.”

But Scherer said that story of how she was shot cannot be true.

“The gun itself doesn’t have a safety, per se,” said Scherer. “So, obviously that is an element that isn’t truthful as far as what was written down.”

Cuellar wrote in his notebook that he drove around in shock and changed her clothes so she wasn’t dirty. Many entries professed love and deep feelings for her and anger that she was seeing other men.

He wrote: “I couldn’t bear to be without her in my life.”

But Phoenix Police confirmed something about the nature of their connection or lack thereof.

“I can tell you there was no element of a romantic relationship at the time of the homicide,” Scherer said.

Cuellar also wrote about how he and the victim shared a daughter.

“We don’t have any information about a child in common between the two,” said Scherer.

Eventually, Cuellar took his own life, and the two bodies were found days later. They were hard to identify due to the condition of their remains.

One of the last notebook entries was this:

“I hope she can forgive me. Please tell my family it was an accident.”

Scherer said a key piece of this puzzle they’re still missing is where she was killed.

While Aguilar was missing, her phone briefly pinged in Peoria, which was believed to be a possible crime scene site.

“Those were never definitive, and a scene was never located,” Scherer said.

While Aguilar’s family and private investigator believe Cuellar’s obsession with Aguilar and his desire for her when he couldn’t have her were the motives, Phoenix PD said they’re still working on that.

“They have their belief as the why. Our investigators are still trying to get to that,” Scherer said.

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