(i do post sometimes, especially since i like finding out potential reasons for why people do things)
i (at the time 16m) dated a girl a few years ago (at the time 15f) who claimed to completely lack empathy. she always talked about how terrible she was and how unlovable she was, and wondered why no one liked her.
when i wasn’t there 24/7, she’d abuse substances, harm herself, and the like. she reported hearing voices, had sleeping issues as well.
she also claims to feel no remorse and outright ghosted me after we broke up. we were friends and she suddenly ignored me when she was 16, i was 17 (female then) and right before we stopped talking i found out she was actually straight, not bi or lesbian, and she would send links to gore websites telling me that they were “funny”, “not that bad”, or that she “didn’t feel a thing”.
Can’t diagnose borderline in teenagers. Personality is not set, hormones are wild, personality disorders aren’t really appropriate models. Hearing voices could be borderline, early schizophrenia (not common in teens, but drug use might play into this), lies for attention… We don’t have enough to suggest that with more evidence (which is always true when we’re weirdos on the internet).
It tends to be thrown around too freely (like how everyone has NPD now) and misdiagnosed in women too imho. I suspect it’s often actually PTSD (sexual trauma) or ASD.
I’m not a psych, but I’ll happily be called out by one.