If there’s anything that gets Catalan nationalists more annoyed that an over-caffeinated tail-gaiting Madrileno, it’s those PP-voting ingrates in Valencia. Most people in Valencia don’t take Valencian (a dialect similar to Catalan, like UK English vs US English) too seriously. People from the small towns speak it, but in the big cities you’d be hard-pressed to find anyone speaking in Valencian (except perhaps the bus tour groups from the villages that are always wandering around looking lost).
Valencia suffered as much as Catalunya did during the civil war (most of Alicante was destroyed, which is why it's such an ugly Franco-ish looking city now), but now is a PP stronghold. Go figure.
To the annoyance of the people in Valencia, Catalan nationalists include Valencia as part of the mythical "Greater Catalunya", although there is little desire in Valencia for seperatism, let alone being ruled from Barcelona. The government in Madrid amuses itself by fanning the flames as much as possible, like for example, issuing official translation both in Valencian and Catalan and (which are written exactly the same).
It’s kind of funny seeing the Catalan separatists suffer from cognitive dissonance when Valencia says they want to seperate from the "Paisos Catalans".