A Rhode Island school bus driver was cleared by a Manhattan jury Thursday in the 1990 Harlem cold case murder of her ex-boyfriend — sparing the suburban mom from potentially spending the rest of her life in prison.

Zunilda Rosario, of Providence, had been plucked from her comfortable New England life to face trial after prosecutors said that nearly 30 years ago, she was a cold-blooded spurned woman who’d gunned down her drug-dealing ex in the lobby of his heroin-infested building.

Rosario, who baked wedding cakes for extra cash, sobbed with her head down on the defense table when the forewoman pronounced her not guilty of Juan Deleon’s murder.

“We are devastated,” said Kathleen Matos, a cousin of Deleon.

Rosario’s two adult daughters and her two sisters leaped out of their seats in the courtroom and cheered.

The afternoon verdict followed less than a day of deliberations and four days of testimony.

On Wednesday, defense lawyers Frank Rothman and Adam Konta argued in summations that prosecutors had failed before trial to turn over a signed, 1990 statement from a key witness.

In the statement, the witness had claimed Rosario knocked on the door to Deleon’s alleged drug den prior to the shooting — an account that contradicts those of other witnesses and what she herself told jurors last week.

“I want to say thank you to everybody,” Rosario said as she left court.

Asked how she felt after the verdict, she smiled broadly, her eyes still red and puffy from weeping.

“Amazing,” she said. “Awesome.”

Asked of her plans for the future, she said, simply, “To drive my school bus.”

Rosario’s daughter, Joevelyn, 29, who turns 30 Tuesday, said, “It’s the best birthday gift.”

The family never doubted Rosario’s innocence, she said.

“Everyone who went up there lied.”

Asked what life had been life, before her mother’s arrest, Joevelyn said, “We had a normal life.

“She had a lot of friends. She worked at the same job for almost 20 years. She has never been in trouble — she’s never even gotten a speeding ticket,” the daughter said.

“She literally has raised us by herself, given us everything that we wanted…and she has done it all by herself. My mom is my hero.”

Rosario, flanked by her family members, then left the courthouse to celebrate the verdict.