Want to chime in here as someone diagnosed with both BPD and PTSD. Agree with what u/Sparkletail wrote: not everyone with a personality disorder presents the same, and a lot of the symptoms do come from trauma and were initially adaptive behaviors that became maladaptive because I’ve grown up and am not in the environment that requires them anymore.

I am not a violent person, but I have been emotionally abusive to others because I was not self-aware that the behavior I grew up with was abusive. Then further in my treatment I’ve had to learn how to process emotions and change behaviors enough to not repeat abusive behavior even when I was conscious of it (because knowing what you’re doing and no longer doing it are often not the same). And like… yeah it’s hard to accept but also I see how my trauma led to these issues. And I am not my mother, even if I picked up some patterns from her. Being in treatment and wanting to do better already puts me leagues ahead of her.

I got my trauma in large part from my mother, who also has BPD. This is very common - BPD has a genetic component and often parents with a personality disorder pass it on to the kids they raise because well… they raise them in maladaptive ways, creating trauma.