The point is the west didn't care about Poland, the Baltics and other states that fell under Russia.
In their mind it was the "price" to pay for relative stability in the west.
The status quo was sealed once Soviet Union has developed their own nuclear weapons using stolen IP. Had this not happened, most likely Stalin would have been pushed back.
Pardon my French, but WTF are you talking about? Stalin took half of Europe.
It confounds me how people think WW2 ended with a success when millions were killed or enslaved as a result of the "victory".