In a less extreme situation, I will make a point of telling the abused crew member that I know that things are not their fault and that I am grateful for everything that the crew does for the passengers. While I don't confront the bully directly, my voice does tend to get a tad louder...hopefully just loud enough for the bully to hear. That way, if they do decide to take it out on me, I can play all inoocent. Although, being a middle aged woman with health problems has some advantages, one being that even most bullies have enough decency not to attack. At the very least, I try to make the victim feel a bit better.