Somthing, I recently did just incase I got depressed. Next time you feel like writing the letters you can do this: get a plain piece of paper. Choose at least 5 word you believe about yourself from a list like this one, get colored pencils, pick 2 of your favorite bright color and a couple of shades between, write all of the words repeating in all directions until the paper is no longer white. After that take a black marker and another page draw and color in an out-line of a person cut out the outline and glue it to the middle of page of words. Hang it in a place you can see it. So no matter how dark you feel you still have all of your good qualities surrounding you. Re-try as needed.