Yes and yes. If the CDU were to ally with AfD then I would squall even more. But they won't- even if it means not gaining power. The SPD will not ally with Die Linke at national level either. So, no parties do not ally with nut case parties at national level in Germany. The last time was when von Pappen thought it was a good idea allying with the NSDAP. That won't be happening again for a long time, if ever. And what has May's alliance with the DUP got to do with proportional representation anyway?