it’s common for people in a relationship to seek to use the power they have to constrict, limit or regulate a partner’s other relationships, in the hopes that this will make those other relationships less disruptive or threatening. People try all kinds of structures to do this: enforced power hierarchies, limitations on how much a partner is permitted to experience emotional or sexual intimacy with others, rules that an established couple will only have sex with a third person if both are there for it (often on the assumption that this will prevent jealousy), and so on.
