Meir gives up hope because of the harsh brutality of the Nazis on a daily basis.
The maintenance of a high moral in any army is a critical factor for its performance. At the moment that Washington selected Valley Forge as the location for his army's winter camp; his army was not equally trained and not well equipped as the British were. So selecting that location made easier for Washington's army to keep a good supply source, a shelter for extreme winter conditions and also a close location from British lines in order to make and prevent incursions.
