From what I understand he was abusive. While that is sometimes and even frequently abused it didn’t seem so in this case.
Plus it sets a pretty bad precedent with a law that is horrendous. Referring to the 20 year automatic sentence.
They were having a verbal argument. He wasn't physically attacking her. She walked out to the garage, got her gun, came back in, said "I've got something for your ass" or something like it, and shot at him.
He had been accused of violence in the past but never convicted of it. She lost her probation for attacking him though. I'd say they were both hot headed and physical. But all that matters is what happened in that house that day.