'I miss him so much': why did a devoted wife kill the man she loved?

Eight years after Sally Challen took a hammer to her husband’s head, a groundbreaking appeal hopes to reveal the truth about their relationshipOn a rainy Saturday morning in August 2010, Sally Challen left her house in Claygate, Surrey. She had bought the house less than a year earlier, her first step away from a 31-year marriage. That morning, she returned to 1 Ruxley Ridge, just around the corner, her former marital home.Though she had told few people, Sally, 56, and her husband Richard,