Stalin's regime was certainly much softer than the Hitler's one ==

Stalin let millions people starve before the war, probably more than the number of Holocaust victims was, so generally Stalin's regime wasn't "certainly" much softer.
If we discuss 1944 in Lviv, it was softer for certain groups, the same for certain ones, and harsher for other ones. It wasn't "liberation" for all. 

In Western Ukraine Red Army was welcome in 1939, Wehrmacht in 1941 and Red Army in 1944. Any of those dates started also a new period of underground activities. 
 

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