Pills may help symptoms but BPD is about perceptions and how we deal with life, so that's not something a pill can fix. It takes work and learning who we are and growing into who we want to be.

Nature vs. nurture? I believe it is primarily nuture and is rooted in attachment difficulties in infancy and young childhood that affect how we view the world. But I also believe that nothing is all one think or another; I think it is both, but mainly nurture.

There are a lot of good books out there about attachment, including "Attachment in Psychotherapy" by David J Smallin.