Brian Laundrie's Notebook Reveals Confession to Killing Gabby Petito: 'I Ended Her Life'

The attorney for Brian Laundrie's family has released a notebook found near Laundrie's body in which the 23-year-old man admits to killing his fiancée, Gabby Petito.

"I ended her life," wrote Laundrie in the notebook, which was found in October 2021 after his death by suicide. (The release of the notebook was reported by Fox News earlier on Friday.)

"I thought it was merciful, that it is what she wanted, but I see now all the mistakes I made," Laundrie wrote. "I panicked. I was in shock. But from the moment I decided, took away her pain, I knew I couldn't go on without her."

In September 2021, the body of Petito, 22, was located in Grand Teton National Park in Wyoming. A medical examiner determined she died by homicidal strangulation. Laundrie, who vanished around the same time amid nationwide calls for his arrest, was found dead from a self-inflicted gunshot wound in the Florida wilderness in October of last year.

In the notebook, which was provided to PEOPLE by attorney Steven Bertolino, Laundrie referred to Petito's death as an "unexpected tragedy."

He claimed Petito was injured while the couple rushed back to their car before it got too dark to see and tried to cross a stream. Laundrie claimed Petito had a "small bump on her forehead that eventually got larger" as well as other injuries, and that she was "begging for an end to her pain."

A lawyer for the Petito family, Patrick Reilly, tells PEOPLE that Laundrie's assertion that the killing was merciful and stemmed from a "tragic accident" is "nonsense."

"He is writing a letter as though he wants people to feel sorry for him," Reilly said.

Asked how the Petito family feels about Laundrie's confession, Reilly says, "I don't think there is anything that can make them feel better about it."

Civil Lawsuit Against Laundrie's Family

Petito's family has brought a civil suit against Laundrie's family. The lawsuit alleges that Christopher and Roberta Laundrie knew the whereabouts of Petito's body during the time in which authorities were pouring resources into a massive missing persons investigation.

Petito's parents, Joseph Petito and Nichole Schmidt, seek more than $30,000 in damages for the mental anguish they suffered due to the alleged deceit of the Laundries. The March filing also alleges that Christopher and Roberta helped Laundrie conceal Petito's murder and were making plans for him to flee the country.

The suit also alleges that instead of helping Joseph and Nichole locate their daughter, the Laundrie parents went on vacation with Brian and ignored pleas for help from Petito's family — and that Roberta blocked Nichole's phone number and Facebook profile in September to avoid contact as Nichole sought answers about what happened to Petito.

"Christopher Laundrie and Roberta Laundrie exhibited extreme and outrageous conduct which constitutes behavior, under the circumstances, which goes beyond all possible bounds of decency and is regarded as shocking, atrocious, and utterly intolerable in a civilized community," the filing, which was obtained by PEOPLE, reads.

At a hearing on Wednesday, Laundrie's parents did not show up to court. Bertolino called the lawsuit "baseless" several times during the hearing, saying his clients were asserting their Fifth Amendment right against self-incrimination.

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"They did what most people would and should do," Bertolino said.

The Petito and Laundrie families entered the national spotlight last summer when Petito's parents reported the young woman missing after she stopped responding to messages while on a cross-country road trip with Laundrie. It was soon revealed that Laundrie had quietly abandoned the trip early and returned to his parents' house in Florida — without Petito.

In the notebook, Laundrie wrote, "I'm sorry for everyone this will affect, gabby was the love of my life… I'm so very sorry to her family because I love them."

He also wrote, "I am sorry to my family, this is a shock to them as well as a terrible greif (sic)."

In an email to PEOPLE accompanying the release of the notebook, Bertolino wrote, "Although I have chosen to release this letter as a matter of transparency I will not be commenting further as there are still proceedings pending in Court."