Depends on your RS and how open your partner is to conflict resolution. It is not a book about BPD specifically,but simply High conflict relationships in general. So you will not be "letting the cat out of the bag" if you share it.
Emphaisis is about how we interact with each other, not how one partner copes with a disordered partner. It is unlikely a pwBPD will take a lot of the ideas on board in the middle of dysregulation, but it could soothe a lot of the interactions before they get to that stage. It will be definitely be of value to you.
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