Sounds like you are in a really tough spot. Lots of people on the boards have been in your position.
Starting with the lessons which can be found on the right side of this forum might help you to understand her behaviors. There is one called Understanding your Partner's behaviors
https://bpdfamily.com/message_board/index.php?topic=56206.msg913187#msg913187If you want to share some of your story, maybe other members can provide some insights or even a "me too" to let you know that you are not alone in your struggles.