I looked into a number of sources regarding this. In Mastering the Core Teachings of the Buddha Daniel Ingram describes this HERE. For Ingram it is an identity crisis where depression, swings in emotion and attention is out of phase with phenomenon. Shinzen Young describes it HERE as a difficulty in integrating the experience of no self, caused by the paper thin-ness of what you thought of as reality. “Everything that has ever given them meaning has now vanished and they flail….”
Is what I experienced a Dark Night? I think the answer is YES. Why? Because the symptoms are the same - I feel a gaping maw unlike anything I have ever experienced before - and I AM prone to depression. It’s like the death of a friend but worse. I’ve felt a dissonance - a syncopation disconnect - like the world and I are half a beat a part. And I didn’t know where to turn, because my identity is wrapped up with the future projected self. It’s definitely a Dark Night, but I got to it in a different way - the meditators usually get to it by deeper Vipassana practice, I got there through self help.
So what do I do now? Ingram and Shinzen both talk focusing on the fluctuations of awareness. Use the weirdness of focus as an object of meditation and realize that in coming to terms with this identity crisis “no self” allows the freedom to create anything you want in its place.
The Atlantic even wrote about this in 2014, and it’s been documented such that The Dark Night Project in Rhode Island exists as a sort of part research project part refuge/halfway house for people going through it, since many people have nowhere else to turn.
And though it does match some of the steps I’ve taken on the insight maps, I came at it from a different way, and I have another way through it potentially. The initial thing that started the Dark Night was contemplating how to “fall in love” with the present.
As my mom said, “You should really work on that”