This is purely anecdotal speaking, but if you strip away the names of the parties, most people I talk to align pretty closely to one of two general viewpoints. Not all people, just on average. There are some issues you’ll disagree with your side on, but typically most people aren’t split so much between two sides they need a third party. Libertarians are probably the biggest third party I’ve seen and they might be close some day to getting on major ballots. As for making parties work together, they should be and that’s sad that they don’t, honestly.