I'm sorry to hear about your sister.
In the case of BPD/EUPD I really don't think it's blame culture. When you've got patients who are denied services, given no legitimate way to access the help they need, blame and dismissal from staff, a culture in services that tell then they are worth as little as they feel... then yes, the finger needs to be pointed at those who let them down so badly.
I had a lovely friend who killed herself after losing hope after years of this arms length non-treatment and blame from mental health services. She had more compassion in one atom of her being than she was ever shown by services over many years. After she died the messages flooded in from so many people, largely online, that she'd supported and helped despite her own difficulties. She was extremely psychologically aware (and educated in psychology) and would have been brilliant at helping others, had she been able to get the help she needed first.
The problem is that there is no way for these people to get the help they need. PPs have mentioned the way services/therapy are only provided if the person will get better fairly quickly. Or crisis services to intercept a suicide attempt, but no ongoing help to get to the root of the troubles and get better. People talk of "cry for help" suicide attempts, but don't stop to think why no-one was listening to the point the person felt they had no other option to make themselves heard.
There is no legitimate (from services POV) way to access the help and support required. There is no way to say "I am overwhelmed and feeling suicidal and need some support, some kindness, because what I'm feeling is terrifying". There is no way, no matter how coherent and logical you may be, to approach services and say "I need some long-term in-depth therapy to give me a realistic chance of hope for the future and prevent the ongoing downward spiral" and actually receive any.
I speak from experience. I had the misfortune of being labelled BPD at the off, and everything that came after was shoehorned in to fit the diagnosis. I have sat in front of mental health professionals scores of times, in sham "assessments" where the pre-determined outcome was always no further input. I have spelled out, calmly and logically, how my issues began (in a way that would have a half-decent psychotherpist already picking at threads to begin unravelling and working through), and how I know I need therapy to recover but without it I see no hope and feel suicidal. And in return I have been judged, labelled, and dismissed.
At some point I had a lightbulb moment, that psychiatry was in the role of abuser, that I kept returning to like a beaten-down woman to an abusive man, who was never going to give me what I needed. That was when the healing really started to begin. (That and having access to things like benefits and reasonable housing so I had a safe place in which to heal.) At some point, I returned specifically for ASD assessment (no professional had ever twigged before) and was diagnosed. My problems stemmed from what I shall call mild ASD (*not getting into that here!) and trauma. In fact, the trauma was the biggest disabling factor. Benefits enabled me to pay for some private therapy. After many years the real deeper healing happened when I found myself in a relationship with the loveliest, most empathetic person, who thought I was wonderful. Somehow I internalised this, and it has lasted far longer than the relationship.
I know services cannot provide the latter (although long-term therapy with an empathetic person who regards them positively is loosely similar in the ways that matter). But I also know that what they do is the precise opposite of this. They judge, belittle, and shame. They actively compound the original problem.
I was one of the lucky ones because I'd had enough good formative experiences, enough safety and care in my life to just about hold on and believe I was worth more than their shitty treatment of me. Interestingly, they hated this. They seemed to want to beat down any self-worth I had, for me to accept their poor judgement of me, to believe I wasn't worth helping and just go away.
Now many years on I have started training to be a psychotherapist. What has really struck me is how it's almost the exact opposite of what services do, the attitudes to the client and so on. And the code of ethics, of the things we strive to be ... would be nice if mental health services had even the slightest attempt at something similar. Someone on another thread wondered why so many MNers want to train as counsellors not mental health nurses - I am sure this is why.
This post has turned out way longer than I thought! But I'd just like to end by saying a big FUCK YOU to all the soulless wankers I encountered in services previously. :)