LATE in November I arrived at the Jesuit Center in the reclusive hills of Wernersville, Pa., on a blindingly dark and stormy night to begin a silent five-day retreat. Such a scenario might have compelled someone more compos mentis to turn around. But that was the point. As a 43-year-old mother of three wrung out from three years of panic attacks triggered by the specter of financial ruin, I needed a solid period of quiet to recombobulate. Cheaply.