Next time you're feeling down, take a break and try to write it out - your fears, your distractions, your insecurities...write it all out.
- Come here and discuss with others.
- Start your own blog.
- Write it all down then burn the paper to banish those feelings from your mind.
- Write poetry.
- Write a song.
- Write an email and then delete it, or send it to someone removed from the situation (try to avoid sending it to your advisor or any peer in your academic community when you're really upset - take a day or so and review what you're trying to say and decide if it will start a productive conversation before you send anything about your Ph.D. Depression)