Sleep deprivation can really depress a person. During a refueling overhaul I was in 102 hour weeks were the norm for Engineering during the last half or so of the overhaul. Seems endless. It really wears you down.
As a BT, I remember putting in a couple 24 straight hour shifts repairing boilers that could potentially hold up our ships evolution. Miserable is all I can find to describe it. Pure misery.
Also, I remember how many marriages broke up in my division alone. (Engineering)
The Navy is not kind to any marriage.
Shipyard periods are a terrible time to be assigned to a ship. All that noise and dirt and long hours. No fun. Ships and sailors belong at sea.