if you lived sat a trillion years the restof the human race would be extinct, and so there would be nothing to live with. and another thing: when you are 80 you are very frail and weak. imagine how week you would be if you were a trillion years old. there would be nothing left of you. and as pararealist said above, after a while you would loose it anyway, so there would be no point. and if you are immortal can you commit suicide?