The South Portland man who police say killed his former boyfriend before turning the gun on himself wrote online of his “dark thoughts” in the hours before the murder-suicide.

Patrick Milliner, 30, shot himself in the head after shooting 22-year-old Matthew Rairdon twice early Saturday, said police, who think that Milliner ambushed Rairdon as he returned to his apartment in Westbrook.

Additional Photos Matthew Rairdon, left, and Patrick Milliner pose together in January. Facebook photo

The men had an on-again, off-again relationship that ended recently, according to a long letter that Milliner posted on Facebook about four hours before the shooting. Milliner indicated that he was upset about the end of his relationship with Rairdon and about spending Thanksgiving alone.

Rairdon was well known in Westbrook, where he was raised in a family of seven children. He was an emergency room nurse who was credited with saving the life of an elderly patient just days before he was killed.

Milliner, a native of California who worked on marriage equality campaigns in two states, moved to Maine in June.

Police think Milliner shot Rairdon very early Saturday morning, when Rairdon returned home from work at Mercy Hospital in Portland. The bodies were found around 11 a.m. Saturday by Rairdon’s female roommate, whom police have not identified.

The shooting occurred in an apartment at the rear of the house at 318 Main St., in a neighborhood about a half-mile from downtown Westbrook.

Maine State Police continue to investigate what they have deemed a domestic violence homicide. They planned to interview Milliner’s classmates at the Maine Criminal Justice Academy, where he was training to be a state corrections officer, and at Cabela’s in Scarborough, where police say he went Friday and bought the .40-caliber pistol that he used to kill Rairdon and himself.

Milliner would have had to pass a criminal background check to be hired by the Department of Corrections, and would have taken basic corrections training with the department before enrolling in the two-week corrections class at the academy.

Rairdon died of gunshot wounds to the head and chest, according to an autopsy done Sunday by the state Medical Examiner’s Office. Milliner’s autopsy showed that he shot himself in the head.

The bodies were found in the entryway to Rairdon’s apartment. There was no sign that Milliner forced his way into the apartment. Police say they think Milliner, who was dressed in black winter clothes, ambushed Rairdon as he opened the door to his apartment.

“The assumption is he had been there waiting for Rairdon to return home,” said Stephen McCausland, spokesman for the Maine Department of Public Safety.

The entry to the apartment is a small space accessed through an exterior door, which is at the top of a short, narrow flight of stairs. A woman who answered the door Monday said she was not Rairdon’s roommate and would not comment about the incident.

In addition to Milliner’s final Facebook post, which made no mention of violence, he left a handwritten note in the apartment where the bodies were found, police said. “The two notes appear to be similar in tone,” McCausland said.

LIFE STRUGGLES, ‘DARK THOUGHTS’

One of Milliner’s Facebook friends with access to his private postings provided the Portland Press Herald with a copy of the long, personal narrative that Milliner posted on the site.

Milliner described a lifetime of emotional letdowns that culminated in his spending Thanksgiving alone. “I cannot count the number of days I have struggled in this life and had dark thoughts,” he wrote.

The 1,900-word piece recounts his parents discovering that he was gay when he was young and reacting poorly, which he said led him to leave home early. Later, his mother was supportive, he wrote.

Milliner also described meeting Rairdon, their first dates and his decision to move from Colorado to Maine to be closer to Rairdon. He said their relationship included several breakups and reunions.

“I am in a dark place again, and this is the last time,” Milliner wrote. “I will not spend another holiday alone like I did yesterday.”

Milliner said he grew suspicious that Rairdon could be seeing other people and confronted him, leading to another breakup.

The most recent breakup came last month, as Milliner started his training at the Maine Criminal Justice Academy. He said Rairdon deleted pictures of the two of them from his Facebook page and removed Milliner as a “friend.”

Milliner said he was tired of looking for “the man of my dreams” and being disappointed.

His letter did not indicate any plans for violence against anyone else, but did suggest that he was contemplating suicide: “I pray that if there is another life after death that it will be free of pain. … I love you all. … I will see you on the other side.”

Shortly after midnight Saturday morning, Milliner surprised Rairdon and shot him, police said.

VICTIM HELPED RESUSCITATE WOMAN

Milliner, whose hometown is Hesperia, Calif., worked on the 2008 campaign to defeat Proposition 8, which banned same-sex marriage in California.

He visited 49 high school gay-straight alliance groups to talk about Proposition 8 and encourage them to talk to their parents about the issue, according to a biography that Milliner posted on the online fundraising website ActBlue.

Milliner posted the description of his experience while raising money to travel to Maine in 2009 to campaign against a ballot initiative to repeal a same-sex marriage law that the Legislature had passed.

Before moving to Maine, Milliner lived in Colorado, where he played in the Colorado Rush Rugby Football Club, which says it provides “an opportunity for men in the LGBT community and their straight allies to play rugby on a competitive level.”

He did not indicate in his Facebook posting when or how he met Rairdon, but wrote that he moved to Maine in June.

Rairdon, a 2009 graduate of Westbrook High School and a graduate of Saint Joseph’s College in Standish, started work recently as a nurse at Mercy Hospital.

Greg Brooks of Gorham said Rairdon was instrumental in saving the life of his 91-year-old mother-in-law last week, when her heart stopped in Mercy Hospital’s emergency room. Brooks called for help from Rairdon, who had just left the room.

“He immediately jumped in there and started giving her CPR and brought her back right before the doctors got there,” Brooks said. “If it wasn’t for him, I don’t know if she’d still be here.”

Brooks said he and his mother-in-law were impressed by Rairdon’s “cool as a cucumber” response to the emergency and how he made his patient feel comfortable.

Rairdon’s father, Gary Rairdon, won election in November to the Westbrook City Council. He was scheduled to be sworn in Monday night but did not attend, said Mayor Colleen Hilton.

Hilton said he will be sworn in as soon as possible after his son’s funeral.

“He needs to focus on his family now,” she said.

David Hench can be contacted at 791-6327 or at:

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Gillian Graham can be contacted at 791-6315 or at:

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Twitter: @grahamgillian

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