This is a VERY complicated area - and nearly impossible to explain a few posts. The gist of this discussion is that we keep wondering how on earth something like DP states could be "caused" by somebody's personality?! (especially when we're all thinking of some really wacked out personalities - likely family members, lol - and THEY don't have these horrible symptoms!)
It is not that any particular personality CAUSES dp. And most of us here are highly likeable, cool personalities - it's not that we're so dysfunctional that people run from us, lol. However, what we might be is HIGHLY CONTROLLED. It's the RIGIDITY of a personality or identity cluster that is the potential contributor for some later breakdown.
One of the key aspects of dissociation is "splitting" - keeping things separate. Partitioning off certain parts of oneself. Some people can do things with one group of friends that might shock other people who think they know that person well. Some of us are good at doing something and sort of thinking "oh, well...this isn't really me, but I can do this..." We split off components of our Self - like a kid playing a game and saying "okay, time out...this doesn't count.." Nothing inherently wrong with this little skill - but it does have a pricetag. And people with narcissistic disturbances tend to be masters at this game.
When we're very good (and rather desperate about) at doing that - separating off parts of ourselves - we are telling 2 things about ourselves: 1) we're good at it because we've perfected the dissociative skill set and probably did so most of our lives without knowing it; and 2) we grew up missing something. Most people as they mature manage to INTEGRATE the different aspects of self into a more cohesive whole. This makes a more stable personality (ego)....makes them less likely to break down. We KEPT the split sense of me/not me as we matured. We, without realizing it, are still juggling PARTS of self, and evaluating/monitoring the self chronically - in short, we're living adult life more the way a young teenager lives life. We lack "groundedness" - we never really feel at home in our own skin, and are always trying on different roles or aspects of ourselves like we were shopping for clothes.
Again, nothing "wrong" with that - but it's a sign that something is VERY rigidly held together, and chances are this person really has major anxiety when dealing with ANYbody - they're never "off guard" and never can just "be"
It's little wonder we later have a breakdown.
Then we get symptoms like anxiety and dp and obsessive thoughts. All we want is to FIX those awful feelings and make them go away and return to our happy little dysfunctional way of being.
Once the dam breaks, we need to really take a look at how we were put together in the first place and work with someone (therapist, ideally, well, for me anyway) to let all the different aspects of self "make friends' with each other...to stop compartmentalizing so much. To stop living so defended. To stop living so Black and White (extremes). To stop fearing other people and needing to control them out of that fear. To learn to "BE" when with other people. That all takes time. And it takes patience. And it takes, fundamentally, a therapist you can really have a RELATIONSHIP with - someone you can learn to be yourself with - that sounds so simple, and for folks like us it is incredibly hard.
And...I know you guys read this and say WHAT DOES THIS HAVE TO DO WITH THE FACT THAT I FEEL LIKE I'M LOSING MY MIND AND THE WORLD LOOKS LIKE A DAMN DREAM EVERY DAY?!?!?!
It has everything in the world to do with it. But I understand that it makes little sense. It made no sense to me either, lol...for many many years.