I think that some people have a more tribalistic view of politics, which involves "us" and "them" dichotomy, much like a professional sports game or war.  The other political side are the bad guys or team.  In sports and war, people don't get outrage fatigue.  Our side is righteous and just, and their side is evil.  They must be vanquished.  Politics is a zero-sum game, and we are going to win it! 
Others may take the view that we are all in this together, and should be working toward certain mutual goals (generally for the greater good), but due to either ignorance or greed, some of the people on our big national team are working to put their own interests first or are being misled by those who are.  Politics feels like being on a giant committee with a bunch of... "difficult people" let's say, who at best make it impossible to achieve anything.  As a result, we are stuck in a really long meeting, working late, and we would rather be at home eating ice cream and watching TV.