What's behind the growing trend of a person, most often a man, killing their own family?

I ’d known Abby for over twenty years. We always had a lot to talk about, with overlapping interests and a similar world view. She had a soothing energy and a keen sense of humour. Over the years, the occasional comment or dark joke made me wonder if we shared the same kind of damage, but I never probed. One day, we sat across from each other in a pub booth in Paddington, a suburb of Sydney, Australia. She ordered a glass of champagne for us both and we picked at some food. After some small talk, she asked me, “How are you?” There was something about her tone, the genuine concern in...