It is believed that Catalonia wants the independence because of funds that they have lost recently. Perhaps it can be one of the reasons. Barcelona is one of the wealthiest regions in Spain. Consequently, a pretty big part of the high taxes go to the poorest regions. Catalonia has always been considered "the industrial heartland of Spain". It's painful to observe how the economic situation is changing. For investors the escalation of the conflict is connected with risk which they prefer to avoid. I spent a few months in a small city near to Tarragona. I perfectly understand why the want to declare independence from Spain. They have their own culture and language what make them feel like a community. The unity makes them strong as if they were a big family. I went to a manifestation during Diada which is the National Day of Catalonia. As its gathers a thousands of demonstrators, the atmosphere there was as unique as their culture.
As far as I'm concerned they will never abandon their attempts to be an independent state. I have to say that some of them are vain and think that Catalonia is better than stinky Spain. Many Catalans didn't want to speak Spanish unless I begged them. Ok, no more malicious comments. During the dictatorship of Francisco Franco it was strictly forbidden to speak Catalan. All the political activity was carried out with only one aim. Destroy the language and customs. Undoubtedly, people became instruments of politics and ideology. 3,500 people were killed at the Battle of Ebro in 1938 because of political ambitions of Franco. This battle is called the bloodiest one of the Civil War.
The truth is that their culture differ from the Spanish one. The Catalan authorities were determined
to achieve theirs goal without bloodshed. As there there isn't a legal basis for treating Catalonia as an independentt state, the situation will deteriorate.