Former liveaboard voyager and self-professed “citizen of the world,” Liesbet Collaert’s memoir Plunge is, like many other voyagers’ memoirs, an account of passages made, life aboard, dealing with gear failure, experiencing tropical beauty and a freedom tempered only by wind and weather. Yet, it would be unfair to only place the book in the category of sailing memoir. Plunge is also an affecting account of Collaert’s emotional life, her evolving relationship with her voyaging husband, Mark, and the losses and trade-offs that everyone, no matter afloat or ashore, must navigate. The memoir is bracingly honest about Collaert’s marriage and the…