In a world more connected than ever, why do so many people feel profoundly alone? Disconnected: The Loneliness Crisis explores how technology, individualism, economic pressure, changing family structures, urbanization, and modern work have transformed the way people build and sustain relationships. Ángel Marqués examines loneliness not simply as a private emotional struggle, but as a growing social, cultural, economic, and public health crisis. Moving across generations and cultures, the book considers the decline of community life, the rise of digital connection, the pressures of achievement, and the emotional consequences of living in societies that increasingly reward independence while weakening interdependence. Drawing on sociology, psychology, neuroscience, history, and public policy, Disconnected investigates how loneliness affects the brain and body, reduces social confidence, deepens inequality, and contributes to anxiety, depression, addiction, cognitive decline, and harmful coping behaviors. From social media and dating apps to workplace isolation, aging, economic hardship, and the aftermath of the COVID-19 pandemic, this book reveals the forces quietly reshaping human connection. Disconnected is a timely examination of what modern life has taken from us—and what must be rebuilt if individuals and communities are to thrive.