This is an EU Problem?

Whilst I obviously disagree with the whole idea of the EU, I do understand the arguments for some things to be handled at a multinational level. The weird thing about the EU however, is this argument is used regularly, and yet when it comes to policies, they nearly all concern things that are very obviously not in this category.

Take this for example

EU countries might in the future adopted a joint course in fighting against domestic violence as experts from 16 countries will meet in Prague next week to prepare a European directive according to which they will deal with the problem.

Could someone versed in the logic of the EU please tell me what it is about the issue of domestic violence that makes it an EU problem? It's as local a problem as you could wish for.