Actually, while the feeling may have been mutual, the national socialist in Germany and the Union of Soviet Socialist Republics did ink the deal to divide Eastern Europe.
Western governments really did not know the extent, but did suspect something bad, and were afraid. There were attempts to try and ascertain what was up.
At the same time, Germany was in part strategically posturing out of fear of the Soviet Union. Hence the effort to ink in a deal for taking the spoils Eastern Europe, even if it was not really the goal.
Stalin was an even more horrific and brutal monster than Lenin, since the death of Lenin in 24.
the western governments had already betrayed and abandoned pathetic Eastern Europe. The Munich Agreement.