If you asked me to

"Are you saying that you married me to merely dig up my mother's corpse?" Sherlock looks down at me. "Of course! Why else would I marry you?" The year is 1912. Sherlock Holmes finds himself in an arranged marriage to Tammy Hake that he can't get out of. She doesn't love him, yet she won't leave him. What secret does she harbor that makes marriage to Sherlock preferable to freedom?