"I will never be able to understand how someone can be ok with knowing they emotionally destroyed someone who did nothing but love them."
Hi Kbagel,
If she has borderline personality disorder, she's probably not capable of even seeing that she destroyed you emotionally.
Don't give her the power to destroy you emotionally. Stay strong.
I also sense her mom chooses her words carefully about her daughter. Saying that"she's acting happy" is very different than "she's happy". If she has BPD, she likely has very unstable emotions.
I would be grateful for the friend who sent you that article.