I've recently started listening to this audiobook: The Body Keeps the Score: Brain, Mind, and Body in the Healing of Trauma by Bessel van der Kolk.

It's very long and I haven't made it very far yet but holy hell it's flooring me. I have to stop listening to it at times because I can't take it, emotionally. It's about trauma, but we all know that trauma plays a huge role in BPD. It specifically discusses the extremely intimate relationship between traumatic events and human physiology. The title really says it all, really. I had no idea scientific research has been able to describe such subtle and dramatic changes in human biology that occur as a response to traumatic events. It's really eye-opening. Anyway, just thought I would recommend this as a useful resource here.