The protagonist should never be driven to an unwanted transformation. An audience will struggle to get behind a passive character who just lets things happen to her. PROtagonists must be PROactive.

I can’t help but think that the husband’s story is way more interesting than the wife’s. He’s got an interesting history, a quest to find the Dead Sea scrolls, and a goal of using that to get his wife back. He is the one being proactive in the story, and in interesting ways. I feel like it’s a story about a man with a tragic history trying to win back the love of his life – just in a very desperate and terrifying way.

Could you start with him as the protagonist but at the midpoint you could flip the whole story and make her the protagonist? The lengths he goes to win her back start becoming increasingly violent and this sets up the wife’s goal of escape.