Your depression may have an identifiable cause. Could be T:E imbalance or something like thyroid or adrenal fatigue. We face this aspects in the T-replacement forum. Go to the one sticky there and in the second post you will find links to what used to be the stickies.
Read the advice for new guys sticky:
prolactin if <=35
CBC with hematocrit
fasting cholesterol [could be too low]
AM cortisol [at 8AM please]
fT4 [please not T3, T4]
Vit-D3 converts to an essential hormone Vit-D25. Please take 5,000iu ED
Get EFA's in your diet
If you do not use iodized salt, you can easily be deficient.
If you want to proceed with the above, start a thread in the T-replacement forum.