Of course it matters. You have a life and as unfair as it is, right now, you're on borrowed time. Prolonging the inevitable. Of course you'll return to Sora one day, but don't you think that while you're here and not able to reach him, that you should live as much as you can? Live life to the fullest! It will make you even stronger, and therefore, he will be all the stronger for it.

I don't know what will happen to you, but a heart never forgets the people that have touched it. Your Roxas isn't truly gone, not really, because you remember him. And I'll remember you.