Also, give up all caffeine immediately. I know it's hard at first but it's the best thing I've ever done for myself. Caffeine sets you up for many mental and physical problems, by raising your homocysteine level and by interfering with the most basic functioning of your whole system (neurotransmitters).
Being caffeine-free is essential for feeling good naturally. My life-long depression only disappeared after about 10 months caffeine-free. Now I never eat chocolate or anything else with caffeine. I used to be a chocoholic and couldn't imagine ever giving up chocolate, cocoa or caffeine. Now I feel so good most of the time, I won't ever allow myself to be so naive again.