I edited that, meant to say the 16th century. Those things happened ages ago, a country can change, you shouldn't generalise like that. It's nice to feel different and that you belong, but in the end we are all the same, made of flesh and bones with similar daily problems. 

I agree, that does not mean I will let other human beings I don't like to decide my future! 

The thing is Cataluña can decide their future, they just have to do it legally by the rules they accepted in 1978. Now they are just doing a rush job, which isn't helping anyone. I guess the objective was to put the constitution in the operating table, and it's something that might happen in the next 6 months.

As Player2 mentioned above, there is corruption scheme deep into the region, with public information coming at the end of the year... maybe that's why their rushing and forcing a push for independence.

So, if a nation inside another nation legally votes to get out (which didn't happen here ofc), you're against it because it leads to division and bad financial consequences?

When the EU asks for futher centralization and someone votes no, would you be against those who stayed out because it keeps division and blocks economic success?

I think that should respect the wishes of the people of Catalonia but I don't see this really going in favor of Catalonia unless it has a sizable military of it's own or have a country with a big military backing them.

Replace autonomous regions with States. That's why I said "pretty much".

Catalonia has never been a standalone nation.

Are you trying to put on the same level the current democratic regime and Franco's dictatorship? Many things were banned during Franco's dictatorship, but Catalonian wasn't one of them (Eduard Punset dixit). It just wasn't an official language, like it happens in Rosellón (Catalonian region under France's control) right now. On the other hand Franco spent more money rebuilding Catalonia after the civil war than any other region.

Less than 50% of the people who voted backed independentist parties last elections (they had less than 50% of the popular vote).

All this has a simple solution. Let Catalunya vote on a legal referendum. That will settle it...

I ask again, why won't they allow it? I'll let you guess...

lol there will always be someone who doesn't like his current prime minister/president/monarch etc.
And that's only on a political level. You can easily transfer that to parents or workplace superiors.

Doesn't mean that all those should just go and create their own state.

I want a referendum. But after clearing all the lies independentists have been spreading for 30 years. Like that Europe will welcome them with open arms, that banks won't leave (already debunked by reality), that bussinesses will fight each other to settle in Catalonia, that no debt will have to be paid, that Spain will pay retirement wages for a few years after Catalonia becomes independent and god knows what more.

Independentists don't seem to be interested either. By acting like this they're killing the only national party that will support a referendum in Catalonia (a party that had five million votes last elections). What they will achieve is more years of Rajoy by making him look good while Rajoy's party corruption goes unnoticed because of all the noise they're making (yay).

EDIT - A more direct answer to your question: Rajoy needs an enemy that distracts people from his corruption. Independentists need an enemy to distract people from their corruption. It seems to be working great so far.