BANGOR — Robert Burton was sentenced Friday to serve 55 years in prison for the murder of his former girlfriend, Stephanie Gebo, in June 2015 in a house they once shared in Parkman.

Burton sat motionless staring directly ahead as justice Robert Mullen imposed the sentence. Mullen said he was tempted to impose the life sentence the state had asked for.

Stephanie Gebo’s father Vance Ginn said that he was satisfied with the sentence, noting that Burton, who is 40, might never get out of prison alive.

Burton was convicted of murder by a jury in October in the shooting death of his former girlfriend, Stephanie Gebo, in June 2015 in her home in Parkman, where they had lived as a couple for more than two years.

Gebo, sleeping with a gun under her pillow because she feared what her jealous ex-boyfriend might do, shot Burton after he climbed through her bedroom window, armed with a knife and black duct tape to bind her until she “admits her wickedness” of cheating on him sexually with other men.

Burton, bleeding from the neck and shoulder, turned the gun on Gebo and shot her from behind, leaving her for dead with three bullet wounds in her back.

Gebo was killed the day after Burton’s probation had ended on a domestic violence conviction that sent him to prison for 10 years. Burton fled after the shooting without seeking medical attention for himself and without calling 911 for Gebo. He turned himself in to police 68 days after what authorities said was the longest and most costly manhunt in state history.

Authorities think he had been living in the woods before he gave himself up at the Piscataquis County Sheriff’s Department, saying he was afraid he was going to be shot.

According to a court affidavit, Maine State Police Detective Micah Perkins found four shell casings from a 9 mm handgun and an open window in the bedroom where Gebo’s body was found. Medical Examiner Margaret Greenwald, who conducted the autopsy on Gebo on June 7, 2015, found multiple gunshot wounds to the lungs, spinal area and trachea and determined the death was a homicide.

Gebo’s body was found lying face down in a pool of blood by her then-13-year-old daughter. The girl got her 10-year-old brother out of bed, then called 911. As she was calling, she saw a camouflage backpack and jacket outside that she recognized as Burton’s. Inside the backpack, police said they later found a knife, duct tape and medication in bottles prescribed for Burton. Police said they found Burton’s cellphone in the jacket.

Burton’s trial lasted nine days in late September and early October and featured Burton testifying on the witness stand. It concluded when the jury of five women and seven men finished deliberating for more than six hours over two days, ultimately rejecting the defendant’s arguments claiming self-defense and having no intention to kill.

Burton, who had a felony conviction for domestic violence and was on probation before moving in with Gebo, also faces a separate charge of possession of a firearm by a prohibited person. He faces an additional five years in prison on that charge. Justice Robert Mullen, who presided over the nearly two-week murder trial, will rule on that charge at a later date.