Just throwing this in the ring but could there be a hormone/pheromone/scent factor going on here? Aside from possibly cold hands or handling protocols, the snake could be really attracted/repulsed by your wife. Do you have other animals or any kids? Are they acting different around your wife? If you notice other entities acting different, then there could be something different about your wife. I had a dog act real funky with me one day and thought he was warning me of a heart attack. Turns out it was a bulging disk causing a pinched nerve in my neck.

Maybe the snake just doesn't like your wife. It could be your very own jealous ball python girlfriend who feels threatened by your wife.