Hi there

bipolar and BPD have many things in common, they can occur to the same person, sadly. I hope you find here the resources and support you are looking for. I'm sure the tools here work for any couple, not just BPD, and learning about BPD you'll find it is not your fault, it's nobody's fault.
Don't ruch into a ton of info. Just check in your own time the basic tools section, and search for questions you may have, or post them here.
There is improvement from here.