There's so much sentiment in this I think is profoundly beneath you, but I want to focus on the most important takeaway.
Your point seems to be that electing leftist Dems will result in disaster for the country. However, I've lived through something like 24 different Congresses in my life now (or at least parts of them), and America has only become more prosperous. Some of these Congresses were pretty liberal, some awful conservative, some fairly centrist. But in all those years, with different ideologies, America is only better off (quite a bit better off).
I don't think the next election will decide the fate of the nation. I don't even think it will be all that big of a deal in the grand scheme of things. Frankly, I think the GOP having become a party of populist idiocy is a much bigger deal than whether Rs or Ds win the next election (or the last one), and even that isn't going to end America (not having a pro-market party could slow our prosperity growth, which I dislike).
You can "Flight 93" all you want (look up Flight 93 election), but I'm not here for it. It's silliness to me, unreflective of reality.