Hi Annelizabeth,
So sorry to hear of the circumstances that bring you here. Having a loved one with BPD traits in our lives can be very challenging to say the least. You'll find you are not alone, as many here either have or are walking in your shoes. I personally do not have experience with a child with BPD, but I am pretty experienced with the illness having had two diagnosed significant others in my life.
We have never been " taught" how to deal with her moods and emotions.
One thing many of us have learned is that we cannot change them (that's up to them), but we can change how we react to and communicated with them. Often times the way we react to or communicate with them simply exacerbates the issue. In the upper right margin of this page you will find some tools and lessons geared to help you improve your own reactions and communication in your situation. Many have found putting these suggested tips into use has improved their circumstances.
Keep posting, you may also want to post your legal questions here:
https://bpdfamily.com/message_board/index.php?board=10.0You've found the right place for knowledge, understanding, and sharing.