Welcome, welcome
Silverstar 
I can guarantee that your post resonates with so many others here...me included! I have years and years behind me that have been filled with the same types of communication from my daughter. Hurtful? You bet! My heart goes out to you.
Although my daughter has been to see many counsellors over the years, to my knowledge she has never been officially diagnosed as having BPD but her behaviours point to that conclusion. What about with your daughter? What is in her history in this regard?
While I echo much of what
Swimmy55 has written in her response to you, I think of how I feel when I see an email come from my daughter...if I don't open it will I take a risk of missing out on heartfelt words from her? We live with hope but we also have to look after our own well-being by setting boundaries...for them...for us.
For sure these loved-ones of ours are suffering internally and are needing to vent. Their first teacher...their Mom...can be a convenient target. I try so hard to see past her obvious illness to the child within, but not so easy to do when "dodging bullets."

Hope you find continuing on here helps you along in this long, difficult journey. There is healing to be found for us in connecting with each other...knowing others are experiencing the same. Also, this website has a wealth of information on how to better move forward to much-needed better days for them...and for us.
((HUGS)

...from Huat