hey stl1984 and
you came to the right place for support and understanding, and i commend you for doing so, as well as seeking therapy as a tool. it comes highly recommended
family and friends do often have a difficult time understanding, and though they mean well and want the best for us, can be invalidating when they encourage us, for example, to move on, or suggest that we should be happy to be out. you are grieving a two and a half year relationship. let yourself grieve .
"Why can't these BPD's understand how they hurt others? What is the disconnect? Why do I find myself breaking my own boundaries with this one specific person?"
the answers to these questions are complex; BPD is a serious mental illness. i strongly encourage you to keep reading, and learn more about the disorder. it can go a long way toward better understanding what we have been through, and even begin to depersonalize our partners hurtful actions toward us. you might start with the lessons we have here, which include "BPD behaviors". you can find the lessons here ---->
https://bpdfamily.com/message_board/index.php?topic=136462.0i also encourage you to keep posting, stl1984. we are a support group, we are here to support you every step of the way, and i can assure you that many members can closely relate to your experience. sharing your experience and relating with the experiences of others will help you to know you are not alone