From everything I have read and comparing her to the way my partner behaves etc. I would say she has a PD I'm not experienced enough to diagnose - although the depressions and thoughts of self-harm seem to suggest BPD I do feel so sorry for you - how involved with her are you? From my understanding BPD's benefit better from therapy than NPD's. If you really love this girl it may be worth seeing if she will consider therapy. It is going to be a hard and rocky road for you and I do wish you all the best