Welcome!
Cultural dynamics definitely add an additional "layer" to BPD issues, and mental health issues, in families. While I don't entirely blame culture on this, I think it has some ties - the expectation of helping and supporting your family no matter what is one that was always very entrenched in my upbringing. We were the full-time caregivers for my ill grandparents throughout my entire childhood - it was expected. This idea has translated down to my parents too. It is expected that I blindly follow and support them no matter what is going on. I had always assumed that the enmeshment and toleration of completely crazy behavior because they were your family was how all families were. I really "broke the mold" by setting boundaries, and eventually going NC with my uBPD mother. I also know that I have learned some not so great behavior patterns from her (a few that are similar to BPD), and am working with my T on "relearning" what is healthy.
The resources and posts here are a wonderful learning tool - I think you'll be able to gain a lot of insight to BPD and methods to use when engaging with your family

I remember when I first was told about BPD and did more research, it was like a light bulb going on.
I will echo Turkish's question - what behaviors are leading you to suspect BPD, and what struggles are you having?