depressed

If you've ever been depressed then you will understand what I tell you. one minute you're sitting there and the next you feel all of your energy and happiness disappear and then you're left feeling dark, sad and scary thoughts. Lately it has been easy for me to get put into a depressing mood and I am left to put on a fake smile and go through the day like nothing is wrong, when really that isnt how I feel and I just want everyoneto leave me alone and go away.
What are you supposed to do when you dont feel a single bit of happiness and yet you dont want to worry the ones who actually care about you....... I haven't been able to find the answer to that but I will tell everyone about it when I find out.....