When I got sick with Covid-19 in early March, I had no idea that I was crossing a threshold. As my symptoms worsened, life seemed to tip on its side, tossing me from the comfort of a well-worn couch—from the steadiness of a body that obligingly did nearly everything I asked of it. I found myself tumbling through a doorway that wasn’t supposed to exist, at least not for me. And still, I imagined that life would quickly pivot again—my body would heal, it just needed a few weeks’ time—and when it did, gravity would deliver me back into the warm embrace of normalcy.