Hello,
I can understand the problem you are facing from such a long time. Recurrent depression can be due to
thyroid,
vitamin abnormality, bipolar mood disorder etc.. Sometimes we miss out hypomania episode as depression covers it. A mood chart will benefit you in that. Adding a mood stabilizer like lithium will cover your bipolar illness and augment your antidepressant treatment as well.
Next Steps
Contact nearby Psychiatric clinic or You can contact me for further help.