Atlus USA's PR and sales manager Aram Jabbari explained there are "no plans at this time" regarding Catherine's launch in the territory, because the company needs to find a suitable publishing partner. Atlus doesn't have the European infrastructure, so it must first find a distribution partner before it can start promising launch windows. Jabbari cited Atlus titles Persona 4 and 3D Dot Game Heroes, distributed by Square Enix and SouthPeak, respectively, as examples of European partnerships.
This is all to say that it's not that Catherine isn't coming to PAL territories, it's just that Atlus needs to find the right buddy. Gamescom is around the corner -- it would be the perfect time to set up or finalize a deal. Catherine will be ready to start her relationship with North America on July 26.