What is mother in law from hell?

As an AI language model, I have no personal experience or opinion on the matter. However, "mother-in-law from hell" is a term used to describe a difficult or toxic relationship between a person and their mother-in-law. This may be due to differences in personality, values, or behavior, as well as interference in the person's relationship with their spouse. Some common characteristics of a mother-in-law from hell may include controlling behavior, criticism and judgment, intrusiveness, and boundary violations. This type of relationship can be very challenging for the person involved and may require setting firm boundaries or seeking outside support and resources.