My girlfriend was diagnosed with BPD like 5 years ago and I went through the same thing. I researched it, found a bunch of really alarming stuff online and freaked out.

We're still together, in a long term, stable relationship, and I want to spend the rest of my life with her. My advice is don't overreact. My psychiatrist's advice, when I asked about it, was essentially that if I had decided I loved her, the new label doesn't really change anything. All it did was create a vague sense of anxiety about the relationship, which turned out to be totally unjustified.

It seems to me that BPD gets a obscene amount of stigma. It is so fucked up that people with BPD are the targets of such frenzied hate, especially on these deranged internet communities. I don't know if it exists on a spectrum and my girlfriend has a mild form or even if it's just a matter of misdiagnosis. (She had been previously diagnosed with Bipolar, but it was changed to BPD after further evaluation). Speaking from my experience, I'd say you shouldn't let it be a deal breaker.

Anyway, fuck the hate from the neurotypicals. You know this girl best and you're the only one qualified to decide how you feel about her.