Hi ONLPM and welcome to the family! I am sorry to hear you are going through this! It is good that you are reaching out for support, BPD management is so often in the little things and the people here on this site are really helpful in figuring those out.
It sounds to me that you are doing the best you can, she communicates after episodes and expresses appreciation. I guess a deeper question is how you cope during her emotional absences? It is hard to accept that our relationships with BPD people involve a lot of periodic loneliness, and it is important to have tools and backups to deal with this.
How is your support network? You have us, what about family/friends/community or religious fellowship? If you focus on building as many of these networks as possible you will feel more secure during the tough times.
In the meantime here is a good place to begin:
https://bpdfamily.com/message_board/index.php?topic=334610.0