Personality Disorders Support Group
Personality disorders form a class of mental disorders that are characterized by long-lasting rigid patterns of thought and behaviour. Personality disorders are seen by the American Psychiatric Association as an enduring pattern of inner experience and behavior that deviates markedly from the expectations of the culture of the individual who exhibits it.
If it's so important for you to stay with her, then I still think you should tell her as much of the truth as you can. Make it clear that you are very reliant on her and that you'll do your very best to follow her advice.
Tell her that you are aware of being hyper sensitive and that you would be glad to change, if she could help you work on that issue (ie. your sensitivity), so that the two of you can go on working together.
You're lucky to have found a nice counsellor.
I know that not everything works for every person, but DBT was a truly healing experience for me and gave me many of the skills I was lacking to deal with being so sensitive, being unable to take criticism, etc. One of the hallmarks of BPD is needing validation from others as we are initially unable to feel validation from ourselves.
I think it would be great if you could let her know about the diagnosis and maybe explore the best path for you to get better.
Good luck! Let me know if you want more info on DBT (what it entails, etc.). I am not a doctor or anything, just someone who has struggled horribly with BPD and is in a better place after DBT.
From my experience, it is essentially about learning to accept ourselves and giving us the tools and skills we need to help regulate the effects of BPD. I attended one skills class a week for 9 months and had individual DBT therapy during those 9 months and for 1 1/2 years after.
My BPD is in "remission." although I will always struggle with it, it has not lead to major depression or destructive behaviors (generally, anyway). I highly recommend it, although quality varies based on the therapist's ability to present information (as always with therapy).
Here is some general info:
http://depression.about.com/od/psychotherapy/a/dialectical.htm