Well, like most things in life, unfortunately there is no right or wrong answer. We don't know what happens ultimately with our conscious selves at the point after death, and that can be debated and discussed till we're all blue in the face. But the fact of the matter is that no one knows for sure. BUT! What we DO know is that we're alive when we're alive. And as redundant of a statement that is it meant simply to focus on now. Tomorrow is something to consider, but you should be focusing on the here and now. Enjoy the life you have at the moment of having it, otherwise it's going to go to waste. And I dunno about you, but I wanna have a good time while I'm still kickin it here on this planet. Sometimes it's harder than others, but screw it. I'm still breathing and I still have my health. Let's get this party started.
Living isn't just breathing. Living is each moment you have and each moment you share. Moments won't last forever, but that's ok. We fight for these moments in our lives, we fight for one last second. Some would rather read a book and some would rather talk to friends, but we all want to experience something, we to experience a moment that can brighten our day and make us feel better. We live for happiness and love, either for others or for ourselves.
Well I personally believe in an after life (I think there's too many near death (or after death) accounts to deny at least the possibility of there being one). However, if I didn't believe in one, I still believe there is a purpose. I don't know. You kind of have to figure it out for yourself. It's that thing that fulfills you to your core. I believe everyone has a purpose. I don't think we would have the desire for something more if it was not possible to be fulfilled by more. Even still, there is the simple joy and love in life that make it worth living. I hope you find joy/truth in some form. I know how annoying it is to obsess over such questions.