In the case of DiRobilland, he was on crutches and still recovering from a stroke. She beat him with his own crutches.
Neighbors found him crawling naked on the street and they had to protect him from her. He later died in hospital.
To be fair, she definitely had the upper hand. From what I understand, they lived together for seven years and it was seven years of hell. Some men are meek and would do anything to avoid a physical altercation.
As mentioned by many of the other men here, in terms of the law it seems men are at a disadvantage. Their best alternative is to walk away from an abusive relationship. The problem is when there are children in the equation. I would not dream of leaving my children with a psycho b#tch. A violent woman will probably also be violent towards her kids.