I got diagnosed with 'emerging BPD' when I was 13/14.
I'm now 19 and feel more secure in my mind than ever, I'm pissed though. I'm pissed that for years after being diagnosed and finding out my diagnosis I thought I was 'different' from everyone else. Little did I know that I was just strong willed and strong minded. 
To anyone out there struggling I would like to say do not label yourself , you probably have all the right reasons to be the way you are due to trauma or other experiences which may have hurt you.
People say it's not treatable it's not curable because there's nothing to cure!
Personally I think people with "BPD" self diagnosed or diagnosed or not are caring individuals who care a little bit too much and it gets them hurt. This is just a speculation I'm not trying to offend anyone. I'm sharing this to hear other people opinion on this matter, nothing more nothing less.