
I’ve been dating this girl for 6 months now and i was wondering if anyone could help me out. The other day, i wanted to workout with my younger sister to show her the ropes and techniques. When i told my girlfriend i wanted to do this, she proceeded to tell me no because she was jealous of her since working was our thing. She then proceeded to insult me by calling me stupid, telling me to go fuck myself, calling me a bitch etc. She claims the reason she acted like that was because that’s how she genuinely felt about the situation and saw it as okay. 

I do want to point out however that a couple months ago she worked out with a male coworker of hers because she was leaving that job and wanted to do it before she left. I voiced my concerns over this even stating how uncomfortable i felt but she proceeded to tell me how she’d be upset if i wasn’t okay with her going.  I just want to know wether or not I’m at fault for this and if her actions are justified. I have no experience being with someone who has BPD so any advice/help is greatly appreciated.