Predictable, surely you jest (tongue in cheek?).
Having lived with a BPD partner for over 20 years, and its consequences, I have observed, lived though and had to manage the unintended but none the less significant and ongoing consequences for the relational bystanders (my kids for a start), you are , maybe making a rather presumptive, presumption. I have a close friend and also staff member who suffer manic depression that I am a support to.
So, assuming you are not being stupidly flippant, you appear to be commenting on matters outside your experience and knowledge. A tricky if not ignorant place. I maybe missing your point of course.
The unfortunately all too many (references to the mass view/convenient assumption and notably with no demonstrable evidence, ignorant and insensitive) opinions in this thread, are equally so.