Hi, I have a diagnosis of BPD. I dispute it though, so the first thing I would say is to read about it and see if it clicks with you. I have 2 friends (who I met in mental health unit) who also have BPD and are (relatively!) happy with their diagnoses.
From our struggles, I would say have you got an advocate? Somebody who can speak for you - partner, parent, sibling...these can be very helpful when trying to access treatment (which is pretty much non-existent where I am).
The only thing that has helped me has been private psychotherapy. When I was stuck in hospital they wouldn't give me any type of therapy, so we managed to find a private psychotherapist who I travelled out to every week. She was great, did a whole combination of CBT, DBT, mindfulness and other stuff. Got me well enough to leave hospital. I had to stop seeing her due to finances though.
I struggle a lot with emotions - controlling them and even recognising them. For a long time I was very mad at myself for having emotions. For example, when I was in hospital and somebody asked about my DC I would cry. No idea why, I didn't feel sad, I didn't feel anything. I was so mad and I suppose embarrassed and disappointed that I was crying, for no reason. But my therapist made me see that actually, being away from my DC for months was actually very sad. And that's ok. It's ok to have emotions.
I've found mindfulness helpful. And grounding techniques for when my thoughts get more and more intrusive and spun-up. (I get very, very intrusive thoughts about hurting myself). Things like looking around and naming something in the room starting with every letter of the alphabet. Or counting forwards in 13s, or backwards from 100 in 3s.
I flit in and out of here as well, depending on how I'm feeling, so sorry if I'm a bit useless.
Hope you're doing ok