Been browsing through this site -
http://www.dictionaryofobscuresorrows.com/ - Basically they're creating new words for emotions that don't currently have them.
Some of my favorites, because they're ones I have frequently:
Lachesism - the desire to be struck by disaster—to survive a plane crash, to lose everything in a fire, to plunge over a waterfall—which would put a kink in the smooth arc of your life, and forge it into something hardened and flexible and sharp, not just a stiff prefabricated beam that barely covers the gap between one end of your life and the other.
Exulansis - the tendency to give up trying to talk about an experience because people are unable to relate to it—whether through envy or pity or simple foreignness—which allows it to drift away from the rest of your life story, until the memory itself feels out of place, almost mythical, wandering restlessly in the fog, no longer even looking for a place to land.
Sonder - the realization that each random passerby is living a life as vivid and complex as your own.
And the most common obscure sorrow I deal with: jouska - a hypothetical conversation that you compulsively play out in your head—a crisp analysis, a cathartic dialogue, a devastating comeback—which serves as a kind of psychological batting cage where you can connect more deeply with people than in the small ball of everyday life, which is a frustratingly cautious game of change-up pitches, sacrifice bunts, and intentional walks.