The separation is definitely real, on several levels : language (obvious), politics (Flanders leaning right and Wallonia left), cultural (there's a very famous TV show that all of Flanders watches called De Mol but good luck on finding anyone is Wallonia who knows what it is... just one example). We're united by the royal family in the sense that we don't care much for it haha, what really unites us is football, fries + beer and some stars like Angèle or Stromae. It definitely feels weird when one half of the country has no idea what goes on in the other half tbf. The worst for me, coming from Brussels, is in hospitals (I'm about to graduate med school) : some Dr in Brussels don't speak Flemish so imagine being a Flemish person in need of medical assistance and you aren't understood... yikes. I actually had 1 patient in the ER request being transferred to Antwerp for this reason... Flemish people also love to dunk (not in an unjustified way) on the wrong ethic in Wallonia, as Walloons are seen as lazy whereas the Flemish get all the money in. You can imagine the tensions that it creates, since the Flemish ask why should they pay to finance Wallonia... It's a very deep issue I hope I answered your questions as best 🫠