I will also direct you to alternativementalhealth.com for information, and to truehope.com for nutritional help. As a psychologist who is also a Christian, I can tell you that Depression like this is ALWAYS multi-factoial -- that it always has a metabolic, allergic, or toxic component, and often a spiritual component as well. If the physical and/or spiritual problems are addressed, then usually the psychological issues take much less time to resolve.
Meanwhile please take care of yourself. I'm sure that many of us will be holding you in prayer