I have only ever heard somebody call somebody else weak when I was in the Army. They used to say it to soldiers who did not live up to some standard or other. Like anything, there were some people whom the shoe fit, because they were unwilling or unable to make a commitment to fix their issues; and some people whom it didn't. I got called weak a bunch of times. Sometimes I deserved it, for being disorganized, sloppy, chronically late, or just plain contrary. Sometimes I didn't. Sometimes it was just plain abusive name-calling, disguised as military toughness and discipline.
When I got called "weak" or any other undesirable thing, I had to consider why the comment had been made and whether it was accurate, and what I wanted to do about it. I really had to do it, because my job depended on it. That taught me some valuable stuff about how to evaluate criticism objectively and when to take it to heart.
Nolongeraslave, I don't share your view that calling someone "weak" (or any other critical adjective) is necessarily verbal abuse. Sometimes it is just calling a spade a spade.