Mr. Body: I can relate at the other side of the fence, since I've been "betrayed" by a BPD friend IRL, 1 week after he tried to hang. I was totally not expecting the move he did on me. It felt so out of context. I'm sure he meant no harm but I couldn't tolerate the concrete outcome resulting from his awkwardness so I cut the tie (I had been supporting him the weeks before, after he broke up with his long-term gf, testifying it's possible).
More reassuring, plenty of BPD sufferers on this board seem to be in relationships (more so than autistic ppl for instance), or have been before, assuming ...more or less... satisfactorily (not meaning to be compared to normal people but you know). Love affairs are a matter of circumstances. Ask Cinderella. Surely, it's ok to vent ! Just don't give up hope?
My own mental condition comes with drawbacks, but not zero benefit. It's principally a curse but also is defining. With BPD, are you all able to value any kind of blessing ? Whether or not it plays a role, my fav SS fellow (& more) has it apparently, which makes me believe there are more dimensions to print the qualities of a person than the mental health status.