Welcome to the family!
If you’ve read SWoE, you’re off to a good start. It’s what led me here. You’ll also find that this site has a real wealth of resources and information that can help you. When you have time, I’d recommended looking around using the links at the top. Reading, posting and asking questions on the boards are also good ideas. We’re here to help and learn from each other.
As to your question, has your wife been diagnosed? Is she aware you suspect BPD? I ask because if the answer is no, we advise NOT telling her. It seems like our loved one would be relieved but that rarely the case. It generally does not go well. If she does know, that’s a different matter.
Regardless, I’d recommend reading this article:
https://bpdfamily.com/content/how-to-get-borderline-into-therapyGetting a pwBPD into therapy — and then them sticking with it through the long, difficult process — is not easy. But there have been success stories.