He's a good fit with a particular personality disorder characterized by narcissism, fragile ego, sociopathy and I think we can add psychopathy here.
In my past and recent life I was involved with sadistic rapists, murderers, serious serial offenders, and pedophiles (both those who did or didn't murder their victims). In my personal life, my narcissism-detecting antennae play a huge role in who I choose to be friends with. One of my close girlfriends is married to a raging narcissist. She is too in love with him to see it. I can hardly bear to be in the same room as him, but I love my friend and she comes first, so I tolerate him without making any issue of it.
I want to be there for my girlfriend when everything falls apart, and it will- spectacularly.
Those of us standing on the periphery often see the bigger picture and the warning signs, which I suspect is what happened with Suzanne and her family. She loved BM and was likely blind to his more worrying traits, perhaps until very recently when things started to unravel.
It's impossible to reconcile how someone seemingly so devoted to her family, beloved by many others, and with a caring and thoughtful approach towards all could meet with such a vile end.
But be assured, BM will have already justified in his own mind the need for him to silence his wife forever. He may never admit it to anyone in confidence (we'll not hear why because that justification doesn't exist in the real world) but it's already there in his mind. He's defiant, and I find that particularly alarming, for reasons I don't want to get into here.
If what we are seeing in public is typical of his behavior in private then I am concerned about what he might be capable of. It's not uncommon for narcissists who have committed heinous crimes to take their own lives rather than face a lifetime in jail. I've known this happen after all their avenues (e.g. appeals) have been exhausted. They prefer to take their secrets to the grave, rather than give grieving family and friends any kind of explanation or genuine show of remorse. It's their final act of selfishness and is intended as such.
MOO