People of all stripes will go to lengths to hold onto their preferred views of things. Re-thinking is difficult and often upsetting to one's equilibrium. But facing reality generally is more effective in life - however painful at times. Upsetting a comfortable equilibrium can also sometimes lead to better things, open up new vistas.
Dr. Sanity has a detailed essay on the topic: DOES THE LEFT UNDERSTAND PSYCHOLOGICAL DENIAL? Even if you overlook the political aspects of her essay, it's a good overview of the points at which psychological defenses and logical error frequently intersect.