OK, where to start. I have a situation, and I'm having trouble separating unhealthy feelings from healthy ones. 

 I recently met somebody in a "life skills" classn who has BPD. In the class we talked about thought and behavior patterns a lot, and everytime this person would open their mouth, I would think to myself "wow,  we're so similar, I think and do the exact same things." Pushing people away before they have a chance to reject me, rejecting a society that seems to reject me,  black and white "if part of the apple is bad the whole apple is bad" splitting.... everything.  There was a point in that class where I spoke a bit about how I think,  and they followed with "I used to think the exact same way and then I realized that was just my brain". They didn't mean anything by it, they were talking about them, but I was shocked and slightly hurt. It felt like a hammer right on the nail. Not long after that I told them that I was terrified that I am also BPD. I looked it up one night and I had to stop.

I started to really like them.  Class with them was safe and fun,  class without them was boring and painful.  It didn't help that the teacher was honestly capable of hurting as much as helping.  Or at least, we both felt that way.  I told them,  awkwardly,  how I felt.  That I was terrified that 

After class (ish),  I took a big step in telling them that I thought they were really cool,  and that they should look me up on Facebook, if they want.  We started talking a lot,  every day. I can see in hindsight that they quickly became my favorite person. I tried to move things towards a romantic relationship and they seemed... I don't know.  Not totally uninterested?  I was psyched.  

Things went very wrong. I could write a novel about how,  and why,  and still not get to the bottom of it.  They went from "cautiously friends" to "done here" to "a boundary was crossed as I spiraled further and further. It ended with me blocked, NC.

I had made some changes to my life a year ago. This - the exact same pattern of diving in head first, of being unable to accept percieved, minor or major rejections, -was not supposed to happen anymore.  

I had a really really dangerous week or two, 
then came to a sort of self diagnosis after reading a lot on wiki and here. I've talked to my psychologist, and they seem to agree, and want me to start DBT group therapy. They offered one option, and I realized that's almost certainly where They attend therapy.  

I don't want to walk in and find Them there. I mean,  part of me desperately does,  but I'm wise enough to at least to recognize that's unhealthy.

I've already tried to... warn them, about this possibility but I'm not sure if they heard or not. I'm so confused.  I don't understand my motivations here.  I don't want to cross a line but I feel like they're getting closr and closer together.  Soon either I risk upsetting them by sending a message on YouTube or someplace where I'm not blocked, or upsetting them by suddenly appearing in their fucking group therapy.  And worst of all, part of me hopes that they'll see me trying to be better,  and that will be the catalyst for at least repairing a friendship (and gleefully,  my brain says,  everything else! ), and I worry that is my ONLY reason for any of this. Part of me hopes that they will see this and tell me what to do! I know I don't want them to be any angrier at me, it feels like if I ever see them again before they are ready it will take another year before they are ready, and this is especially stupid because they have made it clear that's never happening.  

More and more I'm leaning towards the third option, don't go, at least for a while, until maybe they've stopped.  Or, move to a new city.  

Thanks for taking the time to read.  Any insight is really appreciated. I feel like I need somebody to tell me how to not fuck this up,  and then I'll worry about finding the strength to follow through.  I just don't know what I need to do.