Click the quote link to read the discussion. A pwBPD has trouble seeing others as individuals, and will often split someone as all good or all bad, based upon their own past traumas and not fully differentiating themselves from their early caregivers who caused them pain.
Splitting
Splitting refers to a primitive defense mechanism characterized by a polarization of good feelings and bad feelings, of love and hate, of attachment and rejection.
Splitting is a powerful unconscious force that manifests to protect against anxiety. Rather than providing real protection, splitting leads to destructive behavior and turmoil, and the often confused reactions by those who try to help
I'm not BPD, yet my mother's BPD Splitting of me was confusing, and set my emotional table to enter into the relationship with the mother of our kids.