Reading Tusk's comments, perhaps it's true - as Varoufakis recently observed - (don't think he was the first, though) the EU really is like The Hotel California: you can check out any time you like, but you can never leave. He's also been arguing, for anybody who has been listening, pretty much since the Eurozone crisis began, that the task of the European left is to save European capitalism from European capitalists and, by extension, European democracy with it. The authoritarian moves in Poland and Hungary, the rise of Ukip and the FN in France, the Freedom Party in Austria etc, makes it feel at times like we're heading towards a nasty round of xenophobic, right wing authoritarianism populism across the continent.
The EU's task in the near future might be to preserve democracy in Europe from the 'flow' it is currently following. How it goes about it, as it's currently constituted, is another question all together.