Ebenezer Scrooge understood one needs to take care of oneself before it's even possible to take care of anyone else. His problem was that he didn't take the step of investing in his own joy, nourishing his body or his soul, and therefore couldn't be bothered to take care of anyone else.
As opposed to a family scapegoat -- an immediate family member at whom we direct unprocessed anxiety or anger -- a "safe-goat" is a person far enough outside our immediate family system at whom we can direct unprocessed anxiety or anger without inflaming conflicts between present members.
Just like abstaining from carbs will trim your waist in two weeks, trimming three from your family relationships will decrease your load of "dirty laundry" in the same amount of time. Keep it up between now and New Year's Day, and you'll coast through the holidays like Santa on a sleigh.