I'm not diagnosed but have wondered for a while whether I may have ("quiet") BPD. 

I was reading an article and it said: 

"Dr. Perry D. Hoffman, president and co\-founder of the National Education Alliance for Borderline Personality Disorder, explained one of the defining aspects of the disorder in an exclusive interview with HellaWella: “It occurs in the context of relationships. Unlike other psychiatric diagnoses, if you put someone with schizophrenia on an island all by themselves, their mental illness would still be evident. If you put someone with BPD on an island, you wouldn’t necessarily see the symptoms — whatever happens, happens in the context of \[interacting\] with someone else.”

This kind of made me go "woah," and it ties into things I've wondered about with my situation. I've always had social anxiety and been an introvert, but for the past few years especially, I tend to just avoid all but a few close people and focus on trying to hold it together, and in some ways it's been better. I definitely feel numbness, depression, anxiety, etc, but often not as much as I've had at other times and I can at least keep from feeling too much and going crazy. Any time I get involved with new people, though, e.g. trying to get close to or even get to know someone new, or to a certain extent even starting a new job and being with a group of new people, some symptoms get way worse. I've chalked it up to just having bad social anxiety and that maybe avoiding people helps avoid feeling some of the damage of SA on my self esteem, but I don't know.

I always hear about the difference in BPD mood swings being that they're caused by real or perceived interpersonal rejection, but I feel like a lot of the time I just assume rejection so I don't even get involved to take the chance (definitely some AvPD traits). I have such a strong inner critic I feel like at times I'm so constantly thinking negative things or assuming people think negative things about me (admittedly often w/o much evidence) that my brain processes it as rejection, which for sure messes with my moods. 

Does anyone else tend to just avoid people for the most part and kind of, *sort of* do fine, then basically fall apart if/when they get involved with new people? Do some of you struggle a lot even outside of relationships, or maybe even just when being around people in general? For example with acquaintances, or even being fine while hanging around at home, then just a trip to the store makes you feel badly about yourself (far worse than what you'd imagine someone with regular social anxiety would experience)?

Am I just full of shit? 