Part of the reason targets of narcissistic abuse stay in the relationship beyond a reasonable and rational point is because they find it too hard to accept the idea that some people are cunning, devious and heartless. People who are conscientious give manipulators the benefit of the doubt and try to see their side of things.
This is exactly what narcissists and other emotional manipulators count on.
It’s no secret that narcissists target people who possess specific personality traits and vulnerabilities. By definition, vulnerability refers to the inability to withstand the effects of a hostile environment (en.wikipedia.org). Because of this inability to survive in an unfriendly environment, targets of narcissistic abuse distance themselves from painful reality through the use of defense mechanisms which are fairly unconscious, meaning victims use these mechanisms without even being aware of doing so.
Narcissists keep their victims in a constant state of fear, which in turn causes the victim to react from his or her amygdala (or “reptilian” brain). The amygdala controls life functions such as breathing, heart rate and the basic emotions of love, hate, fear, lust, and contentment (all of which are considered “primal emotions”).
It’s also responsible for the fight or flight reaction. Victims of narcissistic abuse live in this state almost every day. Even after the relationship is over, victims suffer PTSD, C-PTSD, panic attacks, phobias, and more…all due to the narcissist triggering their primal fears, including the fear of abandonment. Out of these fears, targets of emotional abuse engage in primitive defense mechanisms including (but not limited to):
Therefore, to answer the question, is it possible he or she is not 100% narcissist, one would need to examine facts, and not come to conclusions based on primitive emotions which may cause one to overlook reality. Has the narcissist been nice at some point in time? Of course they have, because otherwise you would have left them long ago. Those small moments of their “being nice” are simply partial reinforcement, which is the manipulative trick of random rewards to cause you to doubt and overlook their otherwise cruel behaviors.
Did they cry and seem sincere when you threatened to leave? You bet. That’s positive reinforcement, also known as operant conditioning. When they turn on the crocodile tears, apologize excessively, and shower you with gifts after they’ve committed a grievous relationship sin, they are conditioning you to subconsciously look forward to these hoovering attempts, thus triggering you to take them back every time.
In closing, it doesn’t really matter if your abuser is 100% narcissist or not. They could be 80% on the hypothetical scale, they could be 110%. If you are being abused, whether it’s a little or a lot, that makes your partner unfit. The best course of action is to sever the relationship and go No Contact.