Funny thing - UK, US and Russia sold the Poland to Russians (Yalta Conference), and it was right after Western betrayal, where Brits stabbed Poles in their backs, and Ribbetropp-Molotov Pact, where Germany and Russia double teamed Poles. So it's not like they are owed anything.

Sweden actually supported Nazis, mostly by exporting iron ore, and all of that with government's knowledge. Plus they played both sides later, and later helped Allied forces to retake Denmark (funny, because their military strength was deemed too insignificant to count in battle, so only their bases were utilized). So, not only cowards, but also traitors.

You basically have Poles, nation that was doomed from the start (their two neighbours set on destroying them since the beginning of Polish history; their allies willing to betray and sell them without batting an eyelid), and Swedes - never having to face a direct threat, and safely playing both sides.