Adrenal Gland Fatigue - it's what I have after working years of customer service as my day job. It's where your body can't keep up with the stress anymore. Adrenaline is what the body uses as a reaction to the stress, it once helped our ancestors with fight/flight reactions in times of need.
The modern world finds ways of putting us in those stressful situations for hours at a time 5 days a week.
So, what happens when your adrenal glands can't keep up anymore? You basically feel tired and numb all the time. A gray 'veil' over your thoughts, yawning in the middle of the day or feeling still exhausted after a full night's sleep.
I'm fighting it. Not giving in.. taking supplements and a couple of prescriptions.
It will take awhile, but I'll eventually not feel this way.