I always get calls this time of year about depression. My go to herbs for winter depression (Seasonal Affective Disorder) are dried Nettle Leaf and Lemon Balm mixed in even parts in a tea (1 tbsp. mixed herbs for each cup of tea and let steep covered for 3-4 hours). You do not have to drink this tea hot, strain it and drink at room temperature or carry in a thermos to work and sip all day. Drink 2 cups per day and ususally, people see results in less than a week. But, also go outside for 15 mins. or so--even on the cloudiest, coldest days.