Hi Krazydoglady,
Welcome to the BPD Family I'm so glad you decided to jump in and post

Having a BPD Family member isn't easy... .it's downright hard, and it is natural that you wish to have some distance between you and your sister, both because it is the healthier thing to do and because BPD can be exhausting.
In terms of whether or nor you caused your sister's BPD, everything that I have read both here and in books on the subject seem to suggest that BPD is a combination of nature (a pre-disposition of brain development) and nurture (how someone is raised). Not all people with the brain pre-disposition develop BPD and not all people raised in a less than ideal family develop BPD it seems to be the "perfect storm" of both.
So given what we know, I think you can stop blaming yourself for her condition
Here is a link to an article on the cause of BPD... .
https://bpdfamily.com/content/cause-borderline-personality-disorderReaching out here is an excellent way to help improve things with your sister, there are tools here that can help in your communication with her, there are tools like boundaries that can help protect your own well-being, there are tools that can help lower the drama etc... .
Everyone here "gets it" everyone here has someone in their lives with BPD or BPD traits.
I want to point out the box to the right ---> each item is a link to more information so if there is a topic that resonates just click on it for more information.
I found it helpful to read about BPD when I first discovered it, it helped me to get a good basic understanding about what it is, it was helpful to learn the dynamics going on behind the chaos and drama.
In case you are interested two books that I think are good in terms of general information on BPD are... .
Overcoming Borderline Personality Disorder: A Family Guide for Healing and Changeby Valerie Porr M. A.
and
Stop Walking on Eggshells: Taking Your Life Back When Someone You Care About Has Borderline Personality Disorderby Paul Mason, Randi Kreger
Take Care,
Panda39