HALIMA William crossed the desert from Nigeria to Libya hoping to reach Europe for a better life but was forced into prostitution until she was able to escape and find refuge in a rare safe house. The story of William, 23, and her husband Mark, 27, who also faced detention and abuse, show the risks facing ever-growing numbers of migrants seeking what they hope will be safety and prosperity in the West. Though they were reunited by chance at the safe house in the town of Bani Walid, where they have been able to find a semblance of security for…