Discussing politics in the internet age requires careful thought, introspection, and the proper level of hatred for the opposing side. That's why it's important to keep the golden rule of political discourse in mind:
Your own political movement is best represented by its shining stars, its deep thinkers, its models of class and civility, while the opposing political movement is best represented by its dreck, its extremists, its unhinged monsters who commit unspeakable acts of evil.
A lot of people get burned out on politics. And that's because they don't have the proper level of passionate hatred for the other side. This lack of zeal can often be traced to the fact that they see their political foes as human, rather than as the scum of the earth they really are. It's really important to demonize your enemies, so you can get worked up into a frenzy every time they do something.
So any time an unhinged extremist on the other side does something despicable, point at that act of evil as a broad-brush representation of everyone in their political party. Say things like "See? This is the natural result of liberalism" or "Oh, this evil guy was a conservative? What a surprise." Allow acts of terror and evil committed by the other political party to reaffirm your preconceived notions about "those other people" across the aisle.
Meanwhile, if someone aligned with you politically does something awful, do the opposite. Claim the person is "not an actual conservative" or "not a true liberal," and demand that the other side treats him or her as an extremist. Never allow these moments to cause you to examine your demonizing rhetoric. Never rethink your approach of painting everyone who disagrees with you as a Hitler-worshiping Nazi or a Stalin-loving commie.
Because if you do that—if you allow tragedy to affect you as you begin to think of the other side as God's image-bearers—political discourse in this country will be lost forever. Don't let it happen. It depends on you.