The € will not be abandoned. I am pretty sure about it since that would be the detriment of all member states.
Beside, states which want to leave the € behind, at least need to create new laws to establish a new currency (a surrogate for € if you like to say so) with a new exchange rate (fall in value included), have to undergo logistic changes, bureaucratic changes, the private sector will lose its value because it will need to follow the public sector sooner or later, the time needs to be calculated until the new currency will be fully put into place, capital transactions would become restricted again, the right to freedom of movement conditioned too to avoid chaos on the market sector and within the population.
A simple statement like "no, we don't want the € anymore" is not possible by European Law. The €, once granted, is part of the membership. The only way to "abandon" / bypass the € is by creating a state law like described above.
Anyway, one should not forget that the European Union is more than just a common currency. It has a common goal: learning from the past, preserving peace and freedom and stability on the European Continent.