Yep, just because a broken neck would be worse doesn't mean somebody with a sprained ankle should just ignore it. I now have to give props to the psychiatrist who laughed, during my first marriage, when I told him it was "maybe a mild case of wife battering." He said that's like a mild case of pregnancy. Either you are, or you aren't.

I do believe anybody can do something abusive in an isolated incident, having a bad day, and it doesn't necessarily make them an abuser. But if it's a pattern, then it's abuse, no matter how mild compared to something else. A healthy person who does an abusive thing will apologize and learn from it, and not do it again. An abuser may very well SAY, "It won't happen again," but it always does.