I think It needs to be said, and explained: that in that film the husband systematically erodes his wife’s grip on reality by purposely messing with her (adjusting lights, etc, which is the actual term for Gas lighting in psychology now when a person has been driven to question their grip on realiry. Not the new trend where everyone is thinking gaslighting is when you have a day off and boss says “oh don’t take the day off, stay with the team we are family.” That is just manipulation attempt, since you aren’t challenging their reality. Psychologists have mentioned that using gas lighting for every perceived contradiction erodes the term for people whom have actally gone through real gaslighting.