The interest of all EU countries are or should be the same in this situation. What differs is their own experience and history with Russia.
New Eastern members shouldn't fear anything similar happening to them, as any Russian aggression on an EU (or even just NATO) country will prompt an automatic (by treaty) response from other member states.
As for Georgia, if South Ossetia and Abkhazia really want their independence or to join Russia, that is their right. I find it pointless to make war or endure terrorist attacks to preserve a region that strongly wants its independence (other example, the Basque country). It's an aberration similar to a husband going to court in order to fight against his wife's right to get a divorce (and if it fails to sequester her). An UN-sponsored referendum should be held to settle the matter once and for all.