I heard once from a wise woman:
“Hope is like oxygen, you cannot live without either.”
So, just hope that things change for the better, because nothing lasts forever, not even pain and suffering.
And even if you do not care about anything anymore right now, you could still care about something in the future.
We do not know about the future, that is what makes life interesting.
All you can do is have hope, since we do not know.