BRENTWOOD, N.H. — A New Hampshire man was sentenced Friday to 15 to 30 years in prison for a wrong-way crash that killed a retired Massachusetts police sergeant and his wife in January.

Ryan Kittredge, 31, of Derry, was sentenced three weeks after he pleaded guilty to manslaughter and reckless conduct. He was accused of driving drunk and making a U-turn on Route 101 in Epping, causing a three-vehicle crashed that killed John and Heidi Johnson, of New Ipswich. Johnson had recently retired after nearly four decades with the Townsend, Massachusetts, Police Department.

In a lengthy letter to the victims’ family, Kittredge apologized and said he wants to make amends by encouraging others to seek sobriety.

“I sincerely hope that I can somehow communicate to you compassion, sympathy and conviction to make amends in any way possible,” he wrote.

Kittredge told the family that “a few poor decisions in a moment of weakness” have led to a “life full of regret.” In a letter to the judge, he said he doesn’t know whether he started drinking that night to “celebrate yet another long hard day of work” or to run away “from a complicated relationship,” but said he allowed a bartender to “grossly overserve” him that night, even though he only ordered one drink.

“There were three full drinks in front of me when I pushed them away and had enough, but eventually my will power and restraint broke down along with my heart as the pressure to consume and my hopes to forget grew,” he wrote. “I can only expect that some combination of my neurological disorders, long days and sleepless nights and alcohol consumption led to my disorientation and caused this tragic accident.”

Kittredge originally faced 11 charges, including negligent homicide and driving while intoxicated. He negotiated a plea with prosecutors, but had sought a lighter sentence.

Judge Andrew Schulman agreed with the sentence proposed by prosecutors, which also included 7- to 14-year suspended sentences on the reckless conduct charges. Kittredge could shave 2 ½ years off his 15-year minimum if he completes a substance misuse treatment program.