Why do ex girlfriends become nightmares after a breakup?

It’s like she’s made it her personal mission to ruin my life. She was emotionally and physically abusive in the relationship and now even after the relationship has completely dissolved you can’t have an adult conversation with her without her going off the rails calling me a profanity name or threatening me this was cause we are moving out and she has caused damage in the apartment that we both would be responsible for. She treats me like this then runs to her family and friends saying I gaslight her when I call her unstable

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+1 y
I just don’t see the reasoning for being treated like shit
Why do ex girlfriends become nightmares after a breakup?
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