There is absolutely no intention required to abuse somebody. In fact, abuse is rarely intentional. Sometimes it is tolerated, excused, or even thoroughly facilitated by the victim. We all owe each other greater consideration of the material realities of our engagements, and concomitantly a more nuanced and versatile concept of "abuse" that discards today's typical upfront assumptions about a given relationship, and frequently declines absolute individual judgment on disparate elements of a cycle
In other words, analysis of abusive behavior should open our minds to the dialectical inputs and outputs rather than to begin stacking ammunition to make relativistic judgments and erase the disfavored actor and their motives. That's not what stops cycles and ubiquitous social power dynamics.
All you really need to innately understand this is to experience a close relationship with someone where you can't figure out how to stop hurting each other because you both/all have problems that interlock -- which can be as simple as having trust issues after being senselessly betrayed too many times. Much of these phenomena beget themselves in the world.