The histrionics and high drama are a deflection from the truth. Yes, they meant to hurt you. No, they won't ever admit it, and yes, they will make your life a living hell if you try to hold them accountable for their own bad behavior.
A normal person doesn't need to put on theatrics. A normal person has the ability to listen when confronted, reflect, and reason when presented with information that might be less than flattering. Normal people are capable of owning their mistakes and feel genuine remorse if they have done something hurtful. While it is normal to feel mildly protective of one's self-image, normal people do not go need to go to defcon five to protect their egos.
Some toxic people are so steeped in denial that they wholeheartedly believe their own lie that they never meant any harm. Denial is never the same thing as lack of intent. It means that there are a lot of complicated layers of toxic behavior at play. It means they've been playing the game so long they are no longer aware of it.
Those who have experienced prolonged exposure to the manipulation and gaslighting tactics of the dark triad personalities, narcissists, sociopaths, and psychopaths often have extreme reactions to confrontation, too. The difference is that the reaction is a result of having been dumped on by an abuser, not an attempt to dump on others.
Victims of abuse often have extreme stress responses because they are so used to being blamed, manipulated, shamed, and guilted for the behavior of another that they will often brace themselves and automatically absorb guilt and shame for things they are not responsible for. The behavior may appear similar to the drama of a toxic person, but there is one distinct difference: empathy. An abusive person lacks the ability to empathize with the one who is hurt. A victim of abuse is reacting to a double dose of hurt (their abuser's and their own) because they are feeling for two. And, of course, the extreme reaction of a victim is exactly the fuel an abuser uses to twist the situation around to make the victim feel like the hysterical one. Victims of abuse almost always worry (incorrectly) that they are the toxic ones, but abusers almost never recognize or own their toxic behavior.
When someone fails to acknowledge or take responsibility for their toxic behavior, the only healthy option is to get far away from them. No amount of empathy, understanding, or "grace" will turn them around, and in fact, is exactly the kind of behavior they siphon from others in order to stay stuck in their abusive patterns. So long as anyone is willing to enable them, there is no reason for them to change their behavior. Save the empathy, understanding, and grace for their victims.