This article considers the often-neglected role of women as intimate partner terrorists within relationships and explores the ways that female aggression is manifested through psychological as well as physical means of intimidation. Using anonymised clinical material, the author discusses the development of toxic dynamics within an intimate partnership, the pathways through which early traumatic experience creates later destructive re-enactments and how forensic psychotherapy can be undertaken successfully, highlighting the pitfalls. The role of animal cruelty in abusive intimate partner relationships is discussed, with reference to the link between animal abuse and domestic abuse. The function of these violent destructive dynamics to serve as “perverse safe havens” within couples and the wider family systems is outlined. These entrenched dynamics maintain dysfunctional and abusive relationships but the harm they inflict is manifold and when breaking point is reached, forensic psychotherapy can enable essential changes to occur, as the clinical example demonstrates.