Nina Hamberg, whose award-winning book Grip: A Memoir of Fierce Attractions I recently excerpted, answered questions about her motives and process. In the manner of Tobias Wolff’s great memoirs, Grip’s meaning is embedded in its story. A narrative of Hamberg’s fraught relationships with men who are afflicted with their own baggage, Grip is frank sexually without being overly graphic or salacious. Why did you write Grip? I’d never planned on writing memoir. I thought I had a novel in me, …