The United Nations have sanctioned the self-determination right [1]. Quoting wikipedia:
> It [the self-determination right] states that a people, based on respect for the principle of equal rights and fair equality of opportunity, have the right to freely choose their sovereignty and international political status with no interference.
Hence, your argument breaks down at some point. The big issue is how to define that point, because the right definition does not include qualifying criteria for what constitutes "people" and what doesn't.
Based on their strong national identity, pro-separatists in Catalonia consider that they have this right. There are many issues and arguments supporting both sides (although most state-nations are against any kind of wide applicability of the self-determination right for obvious reasons).
In any case, nobody, neither in Catalonia nor elsewhere advocates for that right for your family, your district, etc. because you don't have a national sentiment, you don't feel like a separate ethnic and so on.
We can discuss whether Catalans constitute an ethnicity separate from the Spaniards or not, whether the self-determination right applies in this case or not, and so on... but please don't use the "If Catalans can, my family should also be able too" because it is just derailing the conversation.
> It [the self-determination right] states that a people, based on respect for the principle of equal rights and fair equality of opportunity, have the right to freely choose their sovereignty and international political status with no interference.
Hence, your argument breaks down at some point. The big issue is how to define that point, because the right definition does not include qualifying criteria for what constitutes "people" and what doesn't.
Based on their strong national identity, pro-separatists in Catalonia consider that they have this right. There are many issues and arguments supporting both sides (although most state-nations are against any kind of wide applicability of the self-determination right for obvious reasons).
In any case, nobody, neither in Catalonia nor elsewhere advocates for that right for your family, your district, etc. because you don't have a national sentiment, you don't feel like a separate ethnic and so on.
We can discuss whether Catalans constitute an ethnicity separate from the Spaniards or not, whether the self-determination right applies in this case or not, and so on... but please don't use the "If Catalans can, my family should also be able too" because it is just derailing the conversation.
[1] https://en.wikipedia.org/wiki/Self-determination