Obviously I don't know you personally, but it *is* possible that you could have both borderline personality disorder *and* BP, so that's something to consider too. While I only have BP, I've noticed a handful of people in this forum who have both.
Do you have a therapist who you can talk to? If you do, maybe mention the idea of borderline personality disorder to see what he or she says.
I tend to prefer the idea of treating the symptoms, not the diagnosis. You know what I mean? That may be another way of looking at things.