Do you see a psychotherapist too?
BPD doesn't define anyone, it's just a way to describe how we react/respond to things, the intensity of the feelings that can come along when something upsetting or scary happens.

I was also diagnosed as just depressed for a long time and it never felt right because of the emotional meltdowns I would have - they didn't seem to fit the diagnosis of depression. When the diagnosis of BPD came along, it made sense out of what I experienced. The BPD diagnosis came along several years after I stopped taking anti-depressants. I had been on different medications over the years and was on Prozac at the time I stopped. I stopped for several reasons: one was that I was still feeling depressed a lot so I figured: Take a pill and be depressed or Don't take a pill and be depressed, so it made sense to not take a pill; I also realized as depressed as I was, I couldn't cry, not even when I felt like it could be cathartic - to have a good cry and feel better afterwards; I also was curious as to what I felt like without the emotionally numbing drug - who was I underneath?
So I stopped medication and decided to do just psychotherapy. I have been in therapy for 3+ years and it has helped me in permanent ways, by allowing me to voice my fears and worries and hopes, and see what it is that comes along that interferes and is hard to deal with in my life. We explore it, break it down to see what my perceptions are and if they are accurate, for example. It has really helped me with my relationships.

So I just wanted to offer a non-medication story