This sounds like a moral failing, but independents have to be more active. Voting in the general election usually means holding ones nose and picking the lesser of two evils (and occasional excitement for a great candidate). Historically, the choice was one moderate leaning right versus one moderate leaning left, typically meaning the one with the most charisma got the vote. No more. Like the hollowing out of the middle class in economics, the policy middle has been hollowed out in politics. Neither party seems overly interested in really effective public policy. The most obvious difference is the mastery of propaganda by Republicans--I mean they are really good. "Lock her up" became the mantra for millions. Republicans hammered Hillary Clinton for decades, with great results. Apparently, she flew to Benghazi and personally shot Chris Stevens, then send thousands of classified emails directly to the Kremlin. Democrats cherry pick their information, but seem totally inept at propaganda. They were not even good at promoting their own programs. Republicans eviscerated the Democrats over Obamacare, even thought this form of health insurance is a Republican plan. The Democrats had no good response (at least until Trump became president and the Republicans attempted to kill the program; even then it was mainly outraged citizens who wanted to keep their heath care).
What to do? Get involved. Pick a side. This is hard, given considerable contempt for both sides. Generally, Democrats are the under-performers and too many policies, laws and regulations have moved too far right. Republicans seem to be for tax cuts and deregulation of anything that would hurt corporate profits.