Surely any currency only has value, to the extent that users have trust that it will be a reliable store of value.

Store of value is only one of the possible functions of money. Others are to provide a method of accounting and to provide a medium of exchange. Store of value can be declining at a steady, even increasing, rate yet the money can still be used as a medium of exchange. Just do it quickly. And in a rapid deflation the money can increase in value and not to a beneficial effect.

"It is not necessary to have hope in order to persevere."