Borderlines (especially those with ADD features, which many have), thrive on stimulation. Stimulation can be sought by these people in numerous ways, but arguing or fighting with you is one of the most common.
You've perhaps read in my articles or heard in my videos, that people with BPD traits are energized, enlivened and activated by conflict~ it's why they keep instigating it in your relationship, or continue coming back for more, when history between you has shown it's a reliable outcome.
The inner deadness, flatness or emptiness that people with BPD struggle with at times, is a direct outcome of dissociating from various difficult emotions since very early in childhood (like around 2 years old), so there's a VOID inside, where a litany of different emotions are SUPPOSED to live~ but that they have no access to.
Think of it this way: You're at your favorite supermarket, and as you're strolling around the produce section, half the open bins are empty. Every type of fruit and vegetable represents an emotion (in healing-speak), so if many of them are absent, how can you fill up your shopping cart, and prepare nourishing meals once you get back home?
Borderlines are always too cerebral. They're in their heads analyzing shit all the time, which is why you can feel exhausted when spending time around 'em. They are essentially BRAINS sitting in a plexi-box, hooked up to a mechanical life-support system, which is what makes them hard to treat and heal.
EVERY psychotherapeutic practitioner who's come my way for help, is oriented like this. It takes an act of Congress (just an old expression that once held water) to get 'em the fuck out of their head! BPD within the psychotherapy community, runs rampant~ and so of course, does narcissism.
Core damaged people learned that going up into their head to ANALYZE their pain (figure out why it's there and where it stems from) since they were toddlers, distracted from their anguish. THIS is precisely what has derailed their emotional development. They literally cannot live IN THEIR BODY and endure the emotionally based physical pain that threatens their survival.
Survival strategies like dissociation from emotions we learned during infancy and early childhood remain for a lifetime, because "if it works, keep doing it" becomes our accepted way of life.
BPD isn't about merely changing one's behaviors. It's not about how many years one has been able to sustain a primary relationship.
It's about healing the heart and soul of a client by helping them mend the fragmented self (all the disowned feelings they've been disenfranchised from since early childhood), shredding their defenses which keep REAL intimacy at bay, and teaching them how to build a cohesive, multi-faceted, fully-feeling, self-actualized and healthy Self.
No cognitive or cerebral therapeutic approach grows and HEALS Borderlines, because the wounds they suffered as infants remain on a cellular level IN THE BODY~ not the mind. Highly specialized and focused Feeling Work (which I speak to in my book, DO YOU LOVE TO BE NEEDED, OR NEED TO BE LOVED?) is needed to help these people grow their emotional repertoire, and truly mend.
Who DOES this kind of work today?? Nobody I personally know of, which is a damned shame. There exists an entire population of people with BPD traits and defenses, who will never receive the understanding and help they need and crave to get WELL~ because it's simply not offered.