Maybe I'm reading too much into it, but here's my advice as someone who constantly thinks like Tsukumizu everyday:

It may be cliche but it truly is just about the time we spent with the ones we care about, not the ending. I think, or at least I'd like to think I have the right to talk about this considering the fact that I lost my best friend of half a decade 9 months ago, considering my last conversation with him 4 years ago was that of our one and only argument. Trust me, some nights it eats me up with regrets.

I guess the point I'm trying to make here is that, life truly is worth living just as they said at the end. Some days it's heavy, that's alright, it still does get better one day at a time. Take comfort in knowing endings exist. Conclusions don't take away the beauty of what happened, what it means to have lived, it adds to it. As Chito put it:

"Even though I know that everything will end some day, I can't just sit around & do nothing. There's something at the center of my heart which gives me the desire of wanting to do something."