Life is a journey where goal is not to reach anywhere but to enjoy this journey. You do not have control over its start and end but you have some control on what you do in this journey.
Why to worry for something not in your control rather give your best where you can do something. There will be many situations in life where you will feel like you cannot take more. It may seem you are totally helpless and there is no way out. When you are in such mental state, the first thing you must do is to pull yourself out with some positivity.
The moment you have little hope, you can see at least one small opening somewhere which can help you out. Give your best effort to this little hope. Initially it may look very small with no power or value but it can do miracle for you.
Your one small positive step with little faith can help you to take a big leap. Whatever is the situation, from your side never cut down on your effort. Give your best in any situation what may come.