Bipolar and BPD have some overlap. It's nice to have a diagnosis but really, it comes down to a label and having a label isn't all that important. What's important is treating your symptoms. If you feel comfortable hanging around this part of PC and talking about what you're feeling, then no one is going to kick you out simply because you don't have a diagnosis. It may be possible for you to have both and you'll have to cross that bridge when you get to it. For now, focus on treating the symptoms and that may make things more simple for you.