It seems that fatigue is quite common among people going through some forms of spiritual emergency, and perhaps especially a dark night.
I can see a few possible reasons for such a connection.
A dark night of the soul typically follows a period of high energies running through the system, for instance from an initial kundalini awakening. The system may be “burnt out” from these energies, and needs to rest and so swings back.
If primal fear & dread, or wounds & trauma, surfaces, it can be experienced as overwhelming and lead to temporary fatigue. Similarly, if there is a heightened sensitivity to certain foods, chemicals, environments etc., this may lead to fatigue.
In the fatigue there is an invitation to rest, to quiet the mind and the doing. This may allow the system to reorganize on its own, with less interference from the conscious mind. Here, fatigue functions as a modern form of retreat, or a retreat for those who otherwise wouldn’t easily slow down.
Each of these may apply to me. (a) There was certainly a great deal of energy running through my system from the initial opening, and it lasted for many years. (b) When strong emotions surface, I sometimes feel a bit flattened. Since the initial awakening, my body has been quite sensitive to certain foods, chemicals and environments, and I notice this influences how alert or fatigued I feel. (c) I was very active for years before the fatigue set in (studies, work, community organizing, art, zen and more), and a fatigue may have been one of the few things that could have slowed me down. Fatigue in combination with brain fog has also slowed down my mind, which may allow processes to take place with less conscious interference.
– high energies
– overwhelming wounds/trauma/identifications
– invitation for retreat, rest, quiet the mind and the doing
In talking with people who have gone through a spiritual emergency, and perhaps especially a dark night, and also reading books about it, it seems that some folks experience fatigue during these phases.