Spencer Busby has always wondered what might have been for his pal Dan Broderick and his new bride Linda Kolkena.

In 1989, the successful attorney, 44, and his legal assistant, 28, were gunned down by Broderick’s ex-wife Betty Broderick.

The socialite snuck into his San Diego, Calif., home using their daughter’s key while carrying a Smith & Wesson revolver. She then opened fire at the couple asleep in their bed. Two bullets hit Kolkena in the head and chest, killing her instantly, People magazine reported. One bullet pierced Broderick’s chest. He died shortly afterward.

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Amanda Peet and Christian Slater starred in USA's 'Dirty John: The Betty Broderick Story.' (Photo by Isabella Vosmikova/USA Network/NBCU Photo Bank via Getty Images)

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The shocking murders made headlines and were the subject of two TV movies released in 1992 titled “A Woman Scorned: The Betty Broderick Story,” as well as “Her Final Fury” starring Meredith Baxter.

Three decades later, the infamous case was revisited in the scripted USA series, “Dirty John: The Betty Broderick Story,” starring Amanda Peet and Christian Slater, which aired its finale Tuesday night.

On Wednesday night, Oxygen will further examine the slayings in their long-running true crime docu-series “Snapped.” It will feature interviews with friends of the Broderick family, as well as former detective Terry Degelder and Betty’s attorney Jack Farley.

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Betty Broderick, circa 1991. (Photo courtesy of Oxygen )

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Busby, who was close to Broderick and Kolkena, also participated in the special.

“Dan was ready to move on with his life,” Busby told Fox News. “Him marrying Linda was a pretty clear signal that he wanted to start a new chapter in his life. And he was very torn. He was married to Betty for 16 plus years, so they had all that history. And his decision to move forward with his life was not an impulsive one. He loved his family. But he wanted to help create a better situation for his children. And things just weren’t getting better with Betty.”

“Having gone through a divorce myself, I guess I could understand some of the emotions Betty felt, having that long marriage, investing in that relationship,” he continued. “But you just can’t condone that kind of behavior. You can’t enter someone’s home and expect them to talk to you with a gun.”

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Dan Broderick's pal said the successful attorney was eager to move on. (Photo courtesy of Oxygen)

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Before the slayings, Broderick met then-17-year-old Betty Bisceglia, a freshman at Mount Saint Vincent College, while he was a senior at Notre Dame in 1965, People reported. The couple married in 1969 when Broderick was at Cornell medical school. Ten years later, Broderick, who had a law degree from Harvard as well as a medical degree, had his own medical-malpractice law firm, the outlet shared.

But despite seemingly achieving the all-American dream, Betty resented the fact that Broderick focused on his career, ignoring her and their children. The marriage was disintegrating and, in 1983, Betty accused her husband of having an affair with Kolkena, his newly hired legal assistant. Over the years, some insisted Kolkena resembled a much younger version of Betty.

In one incident, Betty went to surprise Broderick at his office for his birthday and noticed the remnants of a party. When the receptionist told her that Broderick and Kolkena had gone out for the day, she went home and had a bonfire using her husband’s clothes.

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Photo comparison of Betty Broderick (left) and Linda Kolkena (right) with Dan Broderick. (Photo courtesy of Oxygen.)

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It wouldn’t be until 1985 that Broderick filed for divorce. But over the course of nearly five years, their acrimonious divorce became a local legend, E! News reported. In 1989, he married Kolkena.

“From my experience, I would describe their relationship as one of love,” said Busby. “He was certainly captivated by her. She was attractive, yes, but she was also very funny. She had a wicked sense of humor. Dan in general was a very quiet, controlled person. He carried a lot of respect within the community."

"He would sometimes open up when we were having drinks, but he was a more private person," he continued. "Linda was warm and funny. That’s how I remembered her. But if you saw them together, you knew there was a genuine connection. A lot of things have been said about them, but if you got to know them, you would know those comments were unfair.”

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Betty Broderick yearbook photo. (Photo courtesy of Oxygen)

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Busby said the couple rarely brought up Betty and he felt they were “embarrassed” by the ongoing battle.

“Dan was trying to figure out how to deal with the situation, of Betty not letting go,” he said. “He was trained as a lawyer to let the legal system handle it. But it was a struggle. She would leave angry messages with curse words that the children heard. I guess he was hoping that she would move on, too, for the sake of her children.”

Busby said he was stunned after hearing the news of the couple’s murder.

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Dan Broderick (Photo courtesy of Oxygen)

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“I was shocked,” he said. “People always talked about how Dan needed to be careful, but I felt especially sad for Linda. She was very young and had her whole life ahead of her. But she got in the middle of a crossfire that she couldn’t avoid. You don’t ever want to think someone could be so overwhelmed with rage.”

Betty was 41 when she shot her husband and his new wife of six months. Betty has never denied the killing but insisted she had been driven over the edge after suffering years of physical and psychological abuse at the hands of Broderick that occurred even after their divorce. She was convicted of two counts of second-degree murder and sentenced to 32 years to life in prison, People shared.

Betty, now 72, is behind bars at the California Institute for Women. In 2017 her parole request was denied. She is not eligible again for parole until 2032 when she’ll be 84 years old.

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Betty Broderick is eligible for parole in 2032. She'll be 84. (Photo courtesy of Oxygen)

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In 2017, Betty wrote a four-page, handwritten letter to “Murder Made Me Famous” producer Katie Dunn where she expressed frustration at her ongoing incarceration.

“I have no one to speak for me,” Betty wrote at the time, as reported by People. “This was a case of domestic abuse: a pattern of coercive control that lasted throughout my marriage until the day I killed them… Now I am only a political prisoner. They have no reason to deny my parole.”

Busby said there are no winners in this tragic tale. And he hopes that’s the one thing viewers will get from the upcoming show.

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The murders of Dan Broderick and Linda Kolkena are the subjects of Oxygen's 'Snapped: Betty Broderick.' (Photo courtesy of Oxygen)

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“You know, nobody’s perfect,” said Busby. “But they deserved their chance to have a life together. It was cut short and that’s tragic. Betty could have had a fresh start after the divorce and found happiness for herself. She lost control here. But the ones who lost the most here are the children. They lost both of their parents. That’s heartbreaking So much else could have happened here. There are no winners here.”

“Snapped: Betty Broderick,” premieres Wednesday, July 15, at 8 PM ET/PT on Oxygen.