A psychological state characterized by lack of energy.
Energy not available to consciousness does not simply vanish. It regresses and stirs up unconscious contents (fantasies, memories, wishes, etc.) that for the sake of psychological health need to be brought to light and examined.
Depression should therefore be regarded as an unconscious compensation whose content must be made conscious if it is to be fully effective.
This can only be done by consciously regressing along with the depressive tendency and integrating the memories so activated into the conscious mind-which was what the depression was aiming at in the first place.[“The Sacrifice,” CW 5, par. 625.]
Depression is not necessarily pathological.
It often foreshadows a renewal of the personality or a burst of creative activity.
There are moments in human life when a new page is turned. New interests and tendencies appear which have hitherto received no attention, or there is a sudden change of personality (a so-called mutation of character).
During the incubation period of such a change we can often observe a loss of conscious energy: the new development has drawn off the energy it needs from consciousness.
This lowering of energy can be seen most clearly before the onset of certain psychoses and also in the empty stillness which precedes creative work.[“The Psychology of the Transference,” CW 16, par. 373.]
I am sorry you are so miserable. “Depression'” means literally “being forced downwards.” This can happen even when you don’t consciously have any feeling at all of being “on top”! So I wouldn’t dismiss this hypothesis out of hand.
If I had to live in a foreign country, I would seek out one or two people who seemed amiable and would make myself useful to them, so that libido came to me from outside, even though in a somewhat primitive form, say of a dog wagging its tail.
I would turn in rage against myself and with the heat of my rage I would melt my lead.
I would renounce everything and engage in the lowest activities should my depression drive me to violence.
I would wrestle with the dark angel until he dislocated my hip. For he is also the light and the blue sky which he withholds from me.
Anyway that is what I would do.
What others would do is another question, which I cannot answer. But for you too there is an instinct either to back out of it or to go down to the depths. But no half-measures or half-heartedness.
~A letter by C. G. Jung written on 9 March 1959, C.G. Jung, Letters, p. 492-493.