Hi Sam Jones,

I am so sorry to hear about all this. We can help you learn better ways to manage your relationship with your Son (S) and his fiance (GF).
What is the timetable for the wedding?
What does your extended family say about all this?
Do you have other children? Any that are now involved in the drama with the wedding?
How are things with her family? Is her mother suspected BPD as well?
Here is a great book to pick up for more detailed information on BPD:
Essential Family GuideAlso recommend looking at this link to work on communication with your S and his GF:
TOOLS: S.E.T. - Support, Empathy and TruthYours,
mamachelle