I highly recommend this story by Keri Mangis. https://medium.com/illumination-curated/entering-our-dark-night-of-the-soul-e5c617e3fc45. It is far and away the best and most comprehensive explanation of what is meant by and the process of a dark night of the soul that I have had the pleasure to read. I usually eschew what I consider new-age spiritual labeling, however, Keri dives deeply into the meaning behind the label — a must-read in my opinion.