I’m down to zero in my personal life.
It’s a bit painful to remember the people & situations which were a bit like that before.
My favorite tactic is to have nothing at all to do with such people, and to speak up about my assessments of them whenever they come up in conversations with others.
That can be a problem when there is some sort of family and/or professional relationships involved and some people won’t engage the problems and prefer conflict avoidance and hoping the problems don’t exist or will go away or leave them alone if they pretend the person isn’t horrible. In that case, I’ve found the people who will listen and done my best to form covert support groups where we listen to each other and work on what we can do to cope and improve the situation.