I dont agree with the basic premise here. I think most lower and middle ranked officers were still ardent disciples of hitler. though they could see their formations being overwhelmed, none could know that this was happening in all sectors. many believed that hitler was preparing reserves for a massive counterstrike. others believed that terror weapons would turn the tide. Others, more logically believed that hitler would not allow Russian hordes to rape and pillage the fatherland. They fought on desperately, believing hitler would negotiate peace, or somehow achieve victory. perhaps the belief of total victory was gone, but most still believed in the nazi star. Belief in hitler was deep seated and almost unshakeable until the very end.
The fear of unconditional surrender also motivated many to fight on, hoping that something would change.
The high command knew much better, but even they deluded themselves into believeing that they could fight a war of attrition that would somehow demoralise their enemies, and that Hitler would be able to break up the grand alliance ranged against him and make separate peace with one or more of germany's enemies. Throughout germany there was an air of complete detached unreality as to the attitude the world had taken towards them (which was that germany had to be exorcised of its warlike, aggressive, murderous, untrustworthy ways) did not sink in.
It was not so much a refusal to accept the inevitable, as continuing to beleieve the lies put out by Hitler. most still believed in him until the very end. a few continued to do so even after the surrender