It happened near Amsterdam Avenue and West 146th Street in Hamilton Heights around 2 a.m. on Monday, June 10.
Authorities are now searching for 20-year-old Eric Bautista, who they say is the man caught on surveillance video holding a rifle.
Investigators believe Bautista was aiming at another man in a fight over drugs when he fatally shot 40-year-old Winston McKay, who had just finished celebrating the 18th anniversary of meeting his husband and was walking their dog Milton.
Husband Terry Solomon said they had been married for about two years.
"I got the kiss, and next thing I know, I'm getting calls my husband was shot," Solomon said. "I'm questioning myself, like, Lord, why couldn't it have been me? I will never fall in love that way again."
Solomon said McKay and generous and kept to himself, and he wants the gunman to turn himself in to police.
McKay worked as a librarian and was taking college classes at Mildred Elley College in Lower Manhattan. He was shot in the right leg, but the bullet struck his femoral artery.
Solomon said Milton now sleeps by their bed, waiting for Winston to come home.
Anyone with information is asked to call the NYPD's Crime Stoppers Hotline at 1-800-577-TIPS (8477) or for Spanish, 1-888-57-PISTA (74782).
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