So, I don't have BPD but I have a friend who does. I often know when sth she does/says is because of Borderline or not (and if it is I just generally let it slide), but that's not always the case, and I don't always know where to draw the line between BPD traits and actually shitty behaviour (that I'm then afraid to call out).

I don't really know what I'm asking here and I know that this post seems pretty vague, but I just want some insight, thanks.