Couple this with the obscene amount of money it takes to mount a credible campaign, which mostly relies on simplistic 30-second commercials about how awful the other candidate is and how they supported this bill or that bill, and how awful it is that they could compromise on such an important issue (whatever that issue is) and you end up with representatives who spend half their time raising money, a quarter of their time campaigning for re-election by deriding their opponents, and it is no wonder there is little time to even come up with a nuanced version of any issue, much less to foster the kind of across-the-aisle relationships that getting anything done requires.
My solution? Evaluate representatives not on how closely they aligned with your own views on various policy issues, but on how much they actually got accomplished. Did they participate in crafting and passing a more or less realistic budget? Did they reach across the aisle to collaborate with others to get a reasonably good law or policy passed? Did they reach out to ALL of their constituents (not just donors or their "base") with thoughtful discussions and defenses of their votes? Then re-elect them. If they just reacted to the latest 30 second commercial, bowed to pressure from their fellow representatives on their side of the aisle or, worse, their "leaders", vote them out.
At least, that's what I think.