When it comes to Poland, prewar Sanacja regime was completely discredited in the eyes of the Poles for the failure from September Campaign, and the polish government-in-exile was composed of the prewar democratic opposition.
Are you sure about that? When the Soviets invaded Poland under the excuse of "protecting the minorities", Rydz-Śmigły ordered the polish armies to do not fight the Soviets in other situations than in self-defence or to prevent being disarmed, and to negociate with the Soviets the withdrawals of the polish armies to Hungary or to Romania. The polish armies listened and used to surrender their garrisons to the Soviets after being promised to go away. And even after the Soviets broke these promises every single time, even after the massive arrestments and deportations of Poles to Gulag, Sikorski's government-in-exile agreed on 30 July 1941 to restore the diplomatic relations with the Soviet Union in an alliance against Germany. And even after the revelation of Katyń Massacre and the way Stalin ostentatiously broke off the diplomatic relations with Sikorski's government, the Home Army still chose to cooperate with the Soviets in the Operation Tempest in a hope that maybe the Soviets will honour this gesture. They didn't, the Home Army faced the massive arrestments and executions of its key leaders, and even after all of it the Poles still started the Warsaw Uprising with a hope to get help from the Soviets. The Poles didn't receive it, the survivors from Warsaw faced the arresments and executions at the hands of the bolsheviks, and even after all of that, the leaders of the Polish Underground State still agreed to go to the meeting proposed to them by the Soviets (a meeting which in the end ended up with the Trial of the Sixteen).
Shortly said, during ww2 the Poles showed plenty of will to coexist with the USSR. The bolsheviks are those who never honoured it.