Yeah, the community can be pretty crappy. But there are nice people too, luckily. Most of the time you'll run into people who're neither mean nor nice, just not too talkative, those are fine, too.

Rather than restricting yourself to FC-only runs, how about bringing a friend? As a tank you get fast queues, and a DPS player will appreciate that - and as soon as you're 2 people in a 4 player instance, you, in theory, have the option to kick whoever is causing trouble, as long as you kick them first. It's not a fine thing to do, but if you come across someone who's really asking for it, it's a better option than taking their abuse, or being kicked by them. Just make sure not to become an abusive jerk yourself - there's plenty tanks of that caliber out there already.