Abuse doesn’t always leave bruises; it can whisper through control, criticism and isolation. October’s purple ribbons shine a light on the truth that love should never hurt—but too often, it does.

Perpetrators used emotional connection to create a sense of closeness early in the relationship, later using it against their victims.

Researchers found that abusers use a mix of intense affection and emotional cruelty to generate a deep psychological hold that can feel like an “addiction.” ...