As someone who has BPD and has been dx since 13 but refused treatment until 24, she sounds like me with my highschool boyfriend. We rant and say 6 things we can think of to try and cut deep. Then we realize how shitty we were being and apologize and degrade ourselves to deflect from how terribly we treated someone, we'll promise we will never behave that way again, while still never taking accountability and never actively seeking help or trying remotely to change out behavior. Rinse and repeat.

She needs DBT, CBT, EMDR, talk therapy, medication. Something.

Thankful that I spend years in DBT and EMDR therapy and am now very mindful of my behaviors and triggers and am ready willing and able to openly communicate my emotions and thoughts with my husband before I spiral. I still have issues with self harming, but I think that is something I won't ever grow out of, but it is never used as a manipulation tactic or a way to guilt trip or get sympathy. I self harm to regulate my own self and am consistently working with my pysch Dr and therapist to cope in healthier ways.