Her husband murdered three people, injured three more; her world turned insane. Her already frayed family was now shredded, as was the life she knew.

Abieyuwa Odighizuwa’s first instinct was to protect her four young sons, but how was this possible? The oldest, 9-year-old Owa, feared he had rage inside him, like his father, feared he, too, was capable of inflicting harm and causing chaos.

“He was so scared,’’ said the mother, called AB by everyone, dating back to when she was a child in Nigeria. “He was so scared. He told me, ‘Mom, I don’t want to be like my dad.’ And I told him, as long as I’m alive that’s not gonna happen.’

“He was so scared. He was so scared out of his mind. I can’t explain his fears in not wanting to be like his dad. I told him, ‘You’re not gonna be like that if you talk to me. Let’s talk. Whenever you have an issue let me know, I can try to help you if I can. I think that kind of gave him the assurance that he was gonna be OK.’’

Little Owa grew into a strapping young man, a protector of his three brothers and the handiwork of a mother who refused to allow the evil tide to engulf her children, refused to have her boys defined by the horrific actions of their father.

This Mother’s Day, Owa will not be home in Portland, Ore., to be with AB. He just finished his first NFL rookie mini-camp with the Giants, the first taste of the NFL for a chiseled defensive end from UCLA, the Giants’ third-round draft pick. He signed a four-year contract for around $3.4 million and his career is underway.

“It is very uplifting,’’ AB told The Post. “It’s just a validation of my hard work. It just validates that a mother’s hard work is never in vain if you focus on your kids and trust God to guide you, it’s never in vain.’’

Owa knows his mother’s fortitude is the reason he rose out of such a toxic environment, changed but not harmed.

“That’s one thing I want to do in life is make sure she is taken care of and she never has to worry about anything,’’ Owa said. “She did that for us, and I think it’s an honor to be able to give back in that capacity. The things she did and sacrificed, I can never repay with anything that I do. I can try but in my mind I just think if I was in her shoes, could I have done the same thing?’’

There was so much for Owa to overcome. He and his second brother, Ighodaro — called Iggy by everyone — were shipped off to Nigeria when Owa was 3 and Iggy was 2, sent away by their broken-hearted mother, a five-year separation that allowed the boys to escape the indignities of the failing marriage of AB and Peter Odighizuwa.

When the boys were reunited with their parents, they returned to a household that Owa says was “definitely not good.’’ He remembers “a lot of fights in the house, a lot of negativity.’’ And, worse.

“When I was a kid, it’s hard to distinguish abuse from discipline,’’ Owa said. “I think there’s times when my dad may have crossed those lines with all of us. Me personally, I remember getting spanked and things like that, getting hit. As a kid you always think it’s your fault.’’

The marriage was on the rocks. Peter was arrested for assault and battery of his wife, who came out of the violence with a bruised right eye. Five months later, the tragic events of Jan. 16, 2002, unfolded.

Peter was informed he was to be suspended from Appalachian School of Law in his first year because of failing grades. He walked onto the campus in the coal-mining community of Grundy, Va., armed with a .380 semiautomatic pistol and began blasting. He killed the dean, another faculty member and one student, and injured three other students before he was subdued.

In the aftermath, it was determined Peter Odighizuwa, at the time 43 years old, had a history of mental instability. Dr. Jack Briggs, the country coroner, called him “a time-bomb waiting to go off’’ and stated it was “just a matter of him releasing his anger on the world, I guess.’’

After three years of treatment, in 2005 he was found mentally competent to stand trial. He pleaded guilty, avoiding the death penalty, and was given three life sentences, plus an additional 28 years, without the possibility of parole. Peter is serving his time at Red Onion State Prison in Pound, Va.

AB knew her world had become unhinged forever and that she had to get out. She rounded up her four boys, ages 3-9, and headed for New York to stay with one of her brothers in Brooklyn.

“I was concerned about New York swallowing up my kids and taking control, raising my kids for me, and I didn’t want that to happen,’’ AB said.

Two weeks later, the family was on the move again, this time to the Portland area, where AB had lived, briefly, after coming to the U.S. from Nigeria when she was 23 years old. There were cousins living in Oregon, from Peter Odighizuwa’s side of the family, and that is where AB put down roots.

“It was starting all over again, because everything I knew for the past nine, 10 years was gone,’’ AB said. “Starting fresh, like I just came to the U.S.’’

The carnage Peter Odighizuwa wrought “changed a lot of people’s lives, all of our lives,’’ said Roslyn Mitchell, one of Owa’s aunts, who lives in Portland not far from AB and marvels at how one woman held her family together.

“I’m telling you, she needs like an award for being the strongest mother I ever met in my life,’’ Mitchell said. “Very determined. I don’t know how she did it. I couldn’t do it. But she did it. A very, very strong woman.’’

Looking back at that terrible time, Owa says, “I think in a lot of ways the event that happened allowed us to get away from that and get in a better situation. I do believe if my dad was in the house it would have been more destructive than anything.’’

Owa, at a painfully young age, grew accustomed to hardship and separation. Child-care issues and marital instability forced AB, living at the time in Ohio and working in a hospital as a Certified Nurse Assistant, to make the gut-wrenching decision to send toddlers Owa and Iggy to live in her native Nigeria, with their grandmother, Peter’s mother.

“I needed somebody that would be able to take care of the kids properly when I was at work, which was something their dad wasn’t willing to do most of the time,’’ AB said. “It was very difficult. I couldn’t go to a park and watch my kids play. That was one of the most devastating things.

“It helped shape him a lot. In so many ways I can’t even describe. Nothing wrong with being with family, but there’s a difference between being with your parents and being with family members. He had to grow up. It has helped shape everything that he does.’’

During the five years, AB only twice made it to Nigeria to see her boys.

“It was not a very positive experience for me,’’ Owa said of his life in Nigeria. “A lot of physical abuse. Particularly on me. It’s weird. I wasn’t a bad kid.’’

Owa became a student and athlete in Portland and eventually a team captain at UCLA, described by an NFL Draft insider as having “outstanding personal and football character.’’

For a brief period, Owa exchanged letters with his imprisoned father, but there has been no contact for years.

“I can’t recall the last time we communicated,’’ Owa said. “Honestly it’s not a big deal. I feel so far removed from it. It’s me and my brothers.

“I don’t mind, I think for me seeing him wouldn’t mean anything, it wouldn’t be a closure.”

There was nothing shattered because there was not much built up.

“I wouldn’t say he was close to his father,’’ AB said of Owa. “I don’t think it was that kind of relationship, not a father-son relationship there very much. We were too busy involved in fighting and arguing with each other to see the need for that relationship with his son.’’

In Oregon, AB found a hospital job, working a 12-hour shift. Owa became the man of the house at the age of 9. He learned to cook for his three younger brothers on a George Foreman Grill, making sure to call his mother at the hospital if one of the boys wasn’t listening.

Owa never brought trouble home. Once, AB received a call from the elementary school principal, saying Owa had been in a fight. Owa cried, pleading with the principal not to call his mother. The principal implored AB not to punish her son — the fight wasn’t his fault and anyway, Owa already had punished himself enough.

Owa smiles often and easily, flashing a gap-toothed grin, remarkably well-adjusted, considering, well, everything.

“I say my mom was a big part of that,’’ he said. “She fought like hell to make sure me and my brother came back to the states, and she fought again to make sure she separated the boys from my dad. She sheltered us in a lot of ways from a lot of the negative impact most of those situations have on kids growing up. I feel like she’s the main reason all of us came out of that level-headed.’’

There was no player in the NFL Draft displaying a more sculpted body than Owa, who looks as if he is wearing armor. He looks impervious to pain, but sometimes scars form from within.

“He never talks about his dad, none of them talk about their dad,’’ AB said. “That is something I’m not sure if he has any scar or if that is the driving force for him to be who he has turned out to be.’’

AB currently works at a hospice and says her personal restoration began about seven years ago, when she wrote a letter to Peter saying she forgave him.

“You have to forgive for the healing process to begin,’’ she said.

Life moves on, without a companion in AB’s life.

“If any relationship comes in, yes, but right now it’s my kids. They are my No. 1 focus, to make sure they are good citizens, turn out to be good kids,’’ AB said. “That supersedes everything that comes in my life at this point.’’

Of course, her life is different than she ever imagined, but when her world was shattered she instinctively reached out to ensure the safety of her children, no matter what.

“The first thing that came into my head is how am I going to fix these kids?’’ she recalled. “How will I be able to protect these kids? I took them away and we are fine today.

“It’s a story now that I can tell, but the fear and the anticipation of how things were going to turn out was there. You have to be strong when you have little kids that rely on you. If you are not strong they won’t be strong, they won’t be who they are today if I wasn’t strong enough to say ‘OK, this is what we’re gonna do. This is how we’re gonna live our life.’ ”