Here are two things that have helped me with Depression and fatigue:
For Depression - first thing in the morning, drink a 10 oz glass of water with 1 tsp of baking soda dissolved in it. I understand this works by changing the pH of the colon so that serotonin production is enhanced. Whatever the reason, it does seem to help and is simple and cheap.
For energy: Available at your local health food store is a product called Emergen-C that is a powdered electrolyte solution. Each envelope contains 1000 mg of Vitamin C, and the various flavors contain different mixes of other vitamins and minerals. I like to mix a pack each of the cranberry and strawberry flavors in a glass of sparkling water. These two flavors have a good mix of B vitamins.
(I have no reason for recommending this product other than - it worked for me.)