As she tries to pick up the pieces of her shattered marriage to Eliot Spitzer in the wake of his embarrassing prostitution scandal, the state's former First Lady is coping privately with two other family tragedies. Her sister's husband is on his deathbed, according to Trilby Wall, Silda's gracious Southern mom. "Right now, her brother-in-law is dying," the elder Wall told the Daily News. Ray Grayson - the adored 64-year-old husband of Silda's younger sister, Susan - is under hospice care at their Richmond, Va., home. Silda's parents - Trilby and Bob Wall - are by his side as his...