and soldiers that were willing to die for the country and for Stalin.
They were willing to fight and likely die because they knew that if they didn't then they would definately die by their own officers' or forced recruiters' hands. The Soviet military dealt ruthlessly with 'unpatriotric deserters from the greater cause.' Although the Soviet propaganda machine wisely kept its troops informed of German attrocities against Soviet prisonners of war and civilians, which would have strengthened the soldiers' resolve.

Had the western powers attacked the Soviet Union after the surrender of Germany, I doubt they would have pushed the Soviets further back than the German border with Poland before having to push for peace or use the nuclear option. While this would have liberated East Germany and avoided some of the more dangerous exchanges over Berlin it would have given the Cold War much more potential to boil over as there would be many soldiers and officers on both sides who would have seen men die at the other sides hands. A few twitchy trigger fingers and the Cold War could have got very hot indeed with nuclear weapons.

Was anybody really willing to bomb Russian cities with nuke to liberate them from communism?
No, although the Western powers probably would have done so under that justification while the actual reason was to reduce the superior production capacity of the Soviet Union. Prior to the Cuban Missile Crisis there was quite a strong opinion in the American military and even in the Cabinet that a pre-emptive strike against the Soviet Union was in their best interest because the Soviets didn't have a sufficient quality of suitable delivery systems to perform an effective counter strike against America by that point. It probably would've been justified as liberating the Russian people from Communism (by killing them). Sort of like the current administration justifies eroding the freedoms inherent in western democracies in the name of preserving those very freedoms.