what's the meaning of life?

Why do we do the things we do? I can't find a reason that's good enough to keep me doing anything in the long run ...

I think our perceptions of the meaning of life, why we do the things we do and finding reason to keep going can vary from one person to the next. But overall, life is about living and we live by doing things either we or others find meaningful. In my own case, my attitudes and actions in life -- the things I do -- are focused upon being meaningful for others, but some people prefer doing things that at least appear to have meaning more for themselves.

I have no answer, but I'm sorry you feel lost right now

I don't either have an objective answer, but I can say many people will tell you their own, based on their own feelings, interests or values.

Some love feeling selfless and useful for their families, some are hedonistic and deligthed with life's pleasures, some are competitive and dominating and will aim for social status, power, etc. Some will even tell you not to die, thinking out of the economic loss that means (I mean, what a bastard you must be for frauding your parents invesment, all those years of working and consuming your country lost, etc).

If you don't find those feelings that drive you to justify your daily routine, either you grow them by medications and therapy, or you just slowly rot away.