It is difficult with BPD as they are always looking to blame, so often a finger gets pointed at a core issue as responsible for everything, even if it is not.
I think a certain degree of understanding of their condition needs to be reached before realistic assessments of original triggers can be found. Feelings =facts can mean basic feelings of invalidation can be retold as abuse.
I think it is something that evolves in due course, if a T digs too hard, they may very well be sold an excuse.
I have also noticed that even though my partner is diagnosed, any therapists/DRs/councillors tend not to mentioned the label too much as pwBPD can slip into role playing it and using it as an excuse for being the victim, and wanting to blame someone else for causing them to be this way. Someone has to be wholly at fault right?
During early development there is a lot of chicken and egg issues going on. Because they behave "odd", they are treated "odd" and often frustrate those around them who as a result loose patience and act in unsupportive and invalidating ways and so it escalates into a lifestyle of picking squabbles and results in abandonment and "bullies" who fight back.
There can be real abuse, mixed in with imaginary abuse. It is hard to separate them.
Can the core trauma be addressed even is her T doesnt officially see BPD?
It is not just a BPD issue, core trauma is often present in mental illness, most therapy aims at uncovering it and addressing in due course. Without giving it center stage to the point that its hard to get past