I do try. I was raised to believe that losing your cool only hurts your cause. I was also schooled to know that if you are saying something unwelcome your opponent is going to take refuge in anything you do that is less than 100% on the high road.
Keeping my cool is hardest when I feel someone is being manipulative, hurting others, using me, or hurting themselves. I've watched as people have lost their cool, and others kept it, under a lot of provocation. I really get the losing it - even envy it: I'd love to "go off on one" as a friend would say. I can't though, because a lot of people are depending on me not to. "But they deserve it!" is sometimes true. Other times, I don't share the affront but do sympathize.
Once upon a time, parents and other dissidents in the world of eating disorders had no voice at all. Now, there is a voice for almost anyone who wants it, but it isn't always calm or measured or even right. I am in the position of criticizing fellow heretics, and being criticized by association.
No matter how "right" you are, no matter how provoked, it is possible to go too far. In fact, it is probably inevitable. I do cringe, and I do plead with allies to reconsider their attacks. These kinds of exchanges just devolve into competition for being the most victimized and misunderstood. They are a distraction from the issues at hand. But never forget that people who dismiss an idea because there are people who take it to the extreme didn't want to have an honest exchange - they're looking for an excuse to dismiss you. It's best not to give them that excuse, but it doesn't change the responsibility to respond.
MLK was criticized for being too patient, too cooperative, even while he was alive. Yet those wishing to go further, faster, by "any means necessary" at that time seem pretty tame now. Ten years from now ALL of us will be obsolete. Meanwhile, I am more of the MLK school. There are times to shout, times to whisper, and knowing how far to project one's voice effectively is an evolving art.