At the dinner my son invited me to, I froze when I saw a place set neatly at the table — for my husband, who had died two years earlier; when I asked why, my son suddenly turned pale and said, “Mom, there’s something we’ve never told you.” I used to think nothing about grief could surprise me anymore. Then I walked into my son’s colonial-style house in Millbrook, Pennsylvania, carrying an apple pie, and realized I had been naïve. Two years earlier, my husband Robert had collapsed in the north pa