Bitcoin will die. Same with any other currency, if there's no one using it, there's no reason for it to exist.
With no one spending Bitcoins, there wouldn't be any transaction volume. With the no one trading on the market, Bitcoins will be worthless.
I think bitcoin will be really worthless without any users. If there are no demands, then there are low price and and so low users. Wonder what will be the new digital currency that will hit better than bitcoin.