Sometimes we forget that people really need people. From your best friend to a stranger in the street, we all have hard times and we all need a sympathetic ear every once in a while.
Listen. It can be hard to do, people are tempted to give advice which is fine if it is sound, but the best way to support someone is to show them that you care enough to hear them out.
If you can tell that someone is depressed, frustrated, angry, heartbroken, dissapointed... take them aside and listen, chances are they will feel better just to vent.
With all the uncertainty in the world today it is easy for people to get down, if we are going to make a difference in the world, lets start with the people around us!