Why do we keep trying to make everything fit binary systems? Black v. white. Male v. female. Blatantly Aggressive v. Doormat.
Maybe this has escaped notice, but we live in a world of shades of grey. There are very few absolutes, and simple solutions are rarely effective.
And I know exactly why people shy away from genuinely accepting that as reality: it's hard. It's really hard. It means we constantly have to think. About our choices. About our thoughts. About whether or not the knee-jerk reactions we have are coming from reasoned, rational places, from outdated instincts, or from concepts and standards that have been imposed upon us by the society in which we live.
All we can really do is tap into our empathy. Try to understand WHY people are doing what they're doing. You don't have to agree with it, and it's understandable to attempt to change someone's mind, but you also have to respect that, at the end of the day, you may not agree, and that doesn't mean you care about each other any less.
So people are different from you. BIG FECKIN' DEAL. Given how vast and unknowable the universe is as a whole, there's bound to be some pretty awesome variety. How's about instead of focusing on the differences, we focus on the similarities? You like cookies? HOLY SHIT SO DO I!! You dig olives? Not really my bag, but that means there's totally more for you. It. Is. All. Good.
When people say things that sound so freakin' ignorant that they make you want to punch them in their whole face, take a breath. Try to think about why they would say that. Odds are they aren't just trying to get a rise out of you, but rather are speaking either from ignorance or belief (which are not mutually inclusive, thankyouverymuch). Ask them why they think that. Help them to see the fallacy in what they believe rather than smacking them over the head with it. Guide them to the light rather than shining a flashlight directly into their eyeballs.