Notes:

From what I know, the emperor of Nohr (the guy who looks like Emperor Palpatine) apparently killed your father, kidnapped you at a young age, and brainwashed you to think that you're a native of Nohr, likely so that he could control your manakete power. However, your "siblings" were apparently very kind and loving, and you made some good memories and formed a strong bond with them over the years.

However, your real family in Hoshido were apparently worried sick about you and probably thought you were dead. They're overjoyed to see that you're alive, and want you to come home. You undoubtedly have lots of happy memories with them too that are simply locked away by your brainwashing.

And now, you must choose… the family you spent most of your life with and who love you dearly? Or the family you were born into, who never forgot you or stopped loving you even after so many years apart?

Either way, you're going to be breaking the hearts of one of these families. Just completely crushing their hearts into tiny little pieces.