As a transportational cyclist, I'll tell you nothing matters other than getting home alive. Not getting even by whatever means. Not being "courteous" by yielding to cagers. Not being "right". Getting angry at the fools doesn't further this goal and can actually increase the danger. Furthermore, you're not going to educate the ignorant drivers so what is the point? Once you've got your mindset oriented toward the goal of survival you'll be amazed how little these occurences bother you.