It's safe to say 56-year-old Michael Guzzo's ex-wife Janet Guzzo knew him better than anyone.
She told CBS 5 News that Michael Guzzo cut ties with his family more than a quarter century ago after years of mental and physical abuse from his father.
"You either decide to keep your family and resolve it or walk away. He walked away but he still had the anger," said Janet Guzzo.
She met Michael Guzzo at Phoenix College while he was taking classes for pharmacy school. After the two wed she said it became clear that he had mental issues. Janet Guzzo said he refused to get help and drank instead.
"He was isolating, depressed, not talking for five days and rage and anger. Oddly enough I didn't feel in jeopardy," said Janet Guzzo.
Janet Guzzo told CBS 5 News she's not surprised Michael Guzzo took his own life. But was stunned to learn what unfolded prior to his death.
On Saturday, Phoenix police said he gunned down his next door neighbors. They're identified as 66-year-old Bruce Moore, his son-in-law Michael Moore, Bruce's daughter Renee Moore and her son 17-year-old Shannon Moore.
Investigators said after those killings, Michael Guzzo shot into a second home before taking his own life. Detectives believe it all stemmed from the neighbors' barking dogs.
"He must have really decompensated. He must have really started to get paranoid. I will always believe this. That the minute he made the decision to buy that type of weapon he decided he was going to right some wrongs, that people don't listen to me," said Janet Guzzo.
Janet Guzzo said she believes that anything could have set him off. That day it just happened to be the neighbor's dogs.
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