Astonishing Things Have Occurred
Even when his hopes dwindled, John continued to fly the drone and keep a watch on his wife at all times. After a few treks, it got difficult to follow instructions because of the unfamiliarity of the surroundings.
But despite his fears, he had some faith in the future. As far as I can tell, it’s not apparent if she was meeting someone or just taking a different route to work. It wasn’t too late for him to have optimism that everything would go back to normal. Having been married for so long, he was shocked to learn that Donna had cheated on him.