Hey that was some very interesting insight ! It's funny that our experiences would be so different. Seems some misunderstanding went on here.
I could never not concede that every one individual with BPD I have ever encountered didn't go through some form of abuse in childhood. After all, BPD WAS defined to me by each of my therapists as a set of patterns developed following strong relationship trauma anyways and family relationships are the first and most important ones in shaping a person's mental state. In my personal experience it's not such a cliché at all that the abuse usually comes from an unstable mother, in most cases a very controlling, anxious mother. I'm certainly no exception and I am personally convinced that mine has BPD too. My (male) best friend, who I also suspect has it, had a similar relationship with HIS mother, who also checks most cases. I don't know about genetics, since both our mothers come from effed up family dynamics that seemed more influenced by our oppressive national Catholic heritage, but the idea that BPD can totally be caused by an untreated BPD parent is definitely a plausible factor for me.
I agree with the rest of your suggestions, seems you're pretty on point :) I'm sorry I underestimated you :)