Only a woman who has been through postpartum depression can truly, deeply understand.   It's that way with most things, isn't it?  I can certainly empathize and try to imagine what it is like to have cancer, but I haven't gone through it and cannot put myself squarely in that place.  That's why we postpartum mood disorder survivors need each other so, and why so many of us dedicate a portion of our lives to helping other women who will as surely as death and taxes experience the same thing.