You are giving Narcissists way too much credit.
While “cruel” , they are thoughtless in their planning or intensity.
They rarely, if ever, have a plan or premeditated specific activities.
They betray in every way without understanding or empathy to the effect and affect.
They just do the “here and now” like a toddler, whatever feels and looks right for them.
There is no long term thought, feeling or caring with Narcissists.
They do what they want and need to do for themselves when and how they want to with complete disregard for you.
This is what they do and what will always do.
Do your best not to personalise or internalise their behaviours and actions.
It will never add up or make sense to a mature, loving, caring and empathetic person as they are emotional idiots.
And they will return and want you back, so don’t fall for any of it.
They never ever change.
They are blinded by their own sense of omnipotence.
This is their grandiosity at work.
They do something outrageous, but they always believe you will take them back. You always have, why wouldn’t you now?
And anyway they are totally amazing and powerful, and they have figured out all your buttons to push, so all they have to do is push them one more time to get what they want from you.
From the moment they hooked you, they believe you are forever under their control.
They are delusional, remember that.
And they don’t really get that even empaths and codependents have their limits.
We are loyal and loving, yes,sometimes to a fault and we will take a lot, sure, but we will walk away “albeit in a traumatised state”.
They don’t see us as people though, so they somehow don’t get that we have free will, limits and the capacity to leave of our own accord.
And they always underestimate us, always.
Remember that they themselves don’t have limits or moral boundaries so these are alien concepts to them.
We assume that when they do something outrageous like this it’s because they are done with us for good, but that’s just us projecting our own empathic qualities onto them.
They do outrageous stuff simply because they do what they want to do.
They are shallow creatures, don’t forget that.
They want to be perceived as better than you, so they play the victim and smear you.
They have no moral boundaries.
Combine that I-want-this-thing-now mentality with their blinding level of arrogance as to their power over you and they do horrendous stuff without too much thought.
And they don’t see their betrayal as really that big of a deal.
What they did was ‘bad’ but you will take them back.
Which is why when you don’t, they are dumbfounded and experience nuclear meltdowns.