Dr. Brogan was talking about checking B12, Vitamin D, thyroid levels (and some other things I don't remember) and about healing the gut to heal depression. Depression not only post partum but in all stages of life.  Looking back at the other times in my life when I have felt that way, it totally makes sense.  Regardless of the emotional stress that was going on at the time, hormonally and bacterially, something was off that I was blaming on my mind.