I am 40 feet underwater, diving off the coast of Loreto in Baja California Sur, Mexico, when my husband falls from a ladder and suffers a traumatic brain injury at our home in Tampa, Florida, 2,500 miles away.

The scene below the surface is a dream—a drift dive along a volcanic wall waving with soft corals, where eels hang their gaping jaws from nooks and crannies and clouds of yellowtail snap- per flutter past. At the end of the dive, I’m the first to reach the boat ladder, shivering in my wet suit, but I decide to linger on my safety stop to take in the waters that Jacques Cousteau called “the world’s aquarium.”