When Kathy Duva heard Hall of Fame boxer Pernell “Sweet Pea” Whitaker was killed Sunday night after being hit by a car in Virginia Beach, Va., her first thought was, “I hate July.”

Whitaker’s tragic death comes on the 10th anniversary of one of the most heart-breaking months in boxing history. Former champions Arturo Gatti, Vernon Forrest and Alexis Arguello were among eight boxers who died in July 2009, some from ring injuries, some by suicide, and some through criminal or unsolved circumstances that still haunt their family and friends today.

Gatti, a junior welterweight and welterweight champion known for his courage and determination in the ring, was found dead on July 11, 2009, in a condo in Brazil, where he was on vacation with his wife. Gatti, 37, had retired two years earlier.

His wife, Amanda Rodrigues, was initially held as a suspect in his death, but Brazilian authorities ultimately ruled Gatti committed suicide by hanging himself with a bag strap.

Gatti’s manager, Pat Lynch, launched a private investigation on behalf of Gatti’s family into the circumstances surrounding the boxer’s death, but the suicide ruling still stands.

“I still don’t think he committed suicide,” Lynch told The Post on Tuesday. “He was murdered. How and by whom I do not know. But it’s very difficult for me to grasp the fact that he committed suicide. I just don’t see it.”

“That’s hard to let go of,” added Duva, Gatti’s long-time promoter at Main Events. “That was so unnecessary, and I don’t believe he did it to himself, which only makes it worse.”

Forrest, a two-division world champion, was shot to death on July 25, 2009, in Atlanta when he was hit with eight bullets while chasing thieves who had robbed him as he put air in his tires. Forrest was 38 and popular in his community for his charitable work.

DeMario Ware, Jquante Crews and Charman Sinkfield, the shooter, are all serving life sentences in connection with Forrest’s murder.

“He was smart and opinionated,” said Forrest’s long-time publicist, Kelly Swanson. “He had to fight hard to get the championship opportunities he got. His boxing career wasn’t easy. But people genuinely liked him and respected him.”

Arguello was 57 when the legendary featherweight champion committed suicide by shooting himself in the chest on July 1, 2009, in his home in Nicaragua. Arguello, best known for his brutal fights with Aaron Pryor, battled depression.

If alive, Gatti, Forrest and even Arguello would be enjoying the time in their lives when they would be celebrated for their careers. Boxing fans are loyal and love to see their heroes of the past. Whether it’s a Hall of Fame banquet or a mega-fight weekend, boxers of the past are becoming a cherished commodity as the sport tries to link the past with the present.

Whitaker, 55, was a gold-medal winner and one of the best fighters of his era. He was set to make several appearances in Las Vegas this weekend related to the welterweight championship fight on Saturday featuring Manny Pacquiao against Keith Thurman.

“They got robbed,” Duva said. “When you’ve got a legacy like those guys have, you really do get to be that person for the rest of your life and enjoy a lot of things you don’t think about when you’re young.”