Hi lajb000 and

He’s an amazing person with a lot of good qualities; qualities that I have always looked for in a relationship. We’ve been battling back and forth some time now.
If your boyfriend suffers from borderline personality disorder, you should consider that the qualities he exhibits as your boyfriend are only qualities he mirrored in order to solidify your attachment to him.
My own exBPDgf once described herself to me as a "chameleon" which I did see/understand until I realized (much later) that she changed her personality depending upon to whom she attached herself. To me, she was always (or mostly) the woman I fell in love with; but I later saw that she could be very different with other people. This is an aspect of the "identity disturbances" described in the diagnostic criteria. There is a reason why people with BPD (pwBPD) are often compared to sirens (of the Greek mythology ilk).
When we first started I thought that his insecurities were just from the hurt he had from past relationships. He told me he had been cheated on several times by different women. At that time being unaware of what BPD was I put myself in his shoes and empathized with him. I kept trying to prove to him that I was different and wasn’t going to do what others had done to him.
In my observation, pwBPD will perceive *imagined* abandonment even when this is not the intention of their loved ones. Your experience with him could be no different from the experience all these different women went through. It is his disorder which causes him to perceive the threat of abandonment even when it does not exist. And no matter how hard you try, you cannot convince him to no longer be disordered.
I pushed for him to seek therapy and he finally did. He went to a psychiatrist and they diagnosed him with major depression disorder and generalized anxiety disorder. I know i’m not a doctor but I feel like they just didn’t catch the BPD and misdiagnosed it.
Why professionals are reluctant to make a BPD diagnosis is a big debate/discourse. Insurance companies are reluctant to cover mental illness that have poor or questionable outcomes. Many professionals find the disorder difficult to understand and/or treat. The very people who may be suffering from this disorder may be the most resistant to accepting the diagnosis -- so not giving pwBPD the diagnosis right off the bat is a strategy to help pwBPD continue seek help until (hopefully) they are ready to possibility accept this diagnosis.
The other main difficulty with this disorder is that most of the issues are only manifest in intimate/familial relationships. So someone with BPD can be perfectly functional in all other aspects of society - they can be productive and participate... .except when it comes to close interpersonal relationships.
This last time happened about a week ago and I don’t think I can continue in this cycle. I feel extremely affected by it all and have started to feel like I’ve become this co-dependent person in the relationship. He’s aware that he has a problem and wants to seek help for it but he’s only just scratching the surface.
In many ways it is up to him to decide how much he is or is not willing to accept about his condition. And it is up to you to decide how much you can or cannot take in this relationship. You are not responsible for his mental health. You are responsible for your own.
I’ve read success stories in people with BPD and how it is possible for them to overcome it but the only way for that to happen is if they are getting treated specifically for BPD and are going to someone who specializes in it.
But also, treatment can help only if the pwBPD seeks this therapy for themselves. Too often pwBPD enter treatment only in order to stay in their relationship, and when the therapy pushes them too hard, they might just choose to find a new relationship and repeat their cycle.
I hope some of this helps.
Best wishes,
Schwing