Amid all the recent whiplash-inducing developments in the world (pandemics! politics!), one thing has remained stable: People continue to fall in love. Even with the outbreak of COVID-19, applications for marriage licenses actually surged in some parts of the country in February and March last year. Those newlyweds may be on to something. A number of surveys have found that married people are, by and large, happier than non-married people. But as any knot-tier knows, lifetime partnerships aren't simple, nor are they static. "Our love relationships are always evolving," says Helen Fisher, PhD, senior research fellow at the Kinsey Institute and author of