Hello IndoorGardener and

Glad you found the group and felt ready to share. This is a great place to find community and understanding about the unique challenges of having a pwBPD (person with BPD) in your life.
Fifteen years is a long time -- you have certainly invested a lot in your marriage. Do you two have any kids? If so, how old are they, and how have they been doing with the situation?
You mention wanting to work on boundaries for yourself... what's the biggest issue for you there? Do you have a therapist or counselor you're working with at all?
While BPD relationships can be so stressful, we also know that people stay for any number of reasons, and we're here to help you practice new skills and approaches to make the relationship more livable for you.
Keep reading and posting, we'll be here,
kells76