As echoed, such is the life of a healer. Something goes south, even if it's not your fault, you'll be blamed. Not always mind you. Buth healers and tank are often the ones who get the most flack when things aren't going to plan, even if it's somebody else who's messing up. And whilst a healer can help pick up the slack when other people mistakes, there's less room for everybody else to pick up the slack if the healer makes mistakes. Which is why I am happy to help when on my RDM if it's necessary.

if a person is being a douche, handle it as you see fit. Kicking them for harassment can be great, especially if they're a DPS, because of DPS queues. Or reporting for harassing. Or if you can say something witty enough to put them in their place, maybe that can be cathartic and make them think twice. Or just put up with it and just put it down to the luck of the draw. Of course, you could do customer service thing, do the minimal required to do your job.