Why do women become obsessed with the woman that their man cheated with?

I had a fling with a man for about a month until I discovered that he was already involved with someone. I immediately blocked him and hadn’t spoken to him since. Now, three months later, his girlfriend keeps calling me asking me a million questions and keeps checking my social media.

I was nothing to him. Meanwhile she has met his family, he spoils her and takes her on trips, she met his friends and family, and has established something real with her. I was nothing but a dirty little secret. I got nothing from this situation but trauma and a trip to the clinic.

He obviously values her, so why is she so obsessed with me?
Why do women become obsessed with the woman that their man cheated with?
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