Focusing on myself also puts me at odds with my couples therapy, which focuses on bringing us together more, communication, emotions and vulnerability. I can't square the two approaches.
Couples therapy rarely works with BPD as it assume people are willing to work together, pwBPD cant work with anyone, they are who they are and they cant change to harmoniously mesh with someone else, that is the nature of a personality disorder. You need one foot outside just to keep a sense of perspective, if you are too enmeshed you also become dysfunctional as your perspective becomes skewed.
As far as trust is concerned you can only know and predict, as opposed to believe everything you are told.