Not long after my dad died, just after Christmas in 1999, I found myself in the throes of intense grief. I had experienced loss before. Grandparents had passed away. Friends had left me, too. But I had never felt the kind of profound sadness that engulfed me when my father died. It caused my knees to buckle and for months I felt like I was slogging through quicksand, each step muddier than the one before it.