She manipulated you to stay friends with her cause you had a superior role at the job place. She wasn't hiding her ugly side from you because you stuck around long enough she knows you're brainwashed/controlled. It's all about controlling their environment to best suite their needs/wants/desires with no care in the world for the damage it will cause another human.
Once you stand up for yourself, you no longer work like you're supposed to. Thats what we are to them, "objects". Their love is not real, they are not capable of it, its merely deep infatuation. So when a bpd/narc says "i love you" it's more like "I love how you put up with my sh!t, I love how hard you try to please me, I love how you make feel pretty, I love all the validation you give to show me im superior to you, I love how easy you are to control. They love you the same way they love a new cell phone or new purse.
Once the object (you) stops working (being controlled) or calls them out like you did to her, you become enemy 1#. To them it's a "how dare you call me out". Now they will do whatever to bad mouth you (smear campaign) to everyone, create lies, things that didn't happen all to destroy your reputation and make you look like the bad guy and them the victim. Everything is all preplanned in their head. I like to compare them like cancer. The bpd/narc is omitting radiation, being around them heals you, but the longer you stick around it will kill you.
I had so much going on at work with poor mismanagement, I got stuff dumped on me that wasn't supposed to be in my job description, my new manager and I became good friends, the BPD ex hated that (jealousy). My life was chaos, more than I could handle it was getting really hard to keep things together, I was losing my patience and my temper. At the time I didn't know anything about BPD or what it was all I knew was my ex had mental health issues. The stories she told always put her in the victim role, her life was a mess, she has a path of destruction. She is manipulative alright she bragged about manipulating and using people I watched her do it, everything was for her and her only she is really self fish. She wanted to know everything I wouldn't tell her I would keep her in the dark, she is sneaky, digging up info, gathering evidence to use against me, trying to have something to hold over my head. Her and I had intense fights with her having emotional lash outs at me, it was like fighting with a child, she acted like one, she would go to another room to cry. Or we would have a fight over text, she would text so fast I couldn't get a word in edge wise.
The way I seen her treat my replacement was when I seen how sick she really is, I would almost consider it abusive, she used him, she "claimed to love him" I confronted her on it she would get so mad at me. She never got away with the BS with me like she did with my replacement, he stopped talking to me, she controlled his life he was her little puppet. The cancer analogy is a good one, my replacement's heath slowly declined, she almost killed him 6 months ago he had a jammer, four months later she dumped him like garbage, after being with him for 3.5 years. She's single again, heard she is seeing another employee in the corporation. She will have the opportunity to transfer back to the division of the corporation in my town in the next 2 months or so, I just hope she stays away from me.
If I was still around the ex as a friend I prolly would be dead, enough was enough, she kept causing drama in my life, picking fights with me, jealously when I approached other women at work, fvcking with my personal life. I know a lot about BPDs today, I know now she's a BPD, took me a long time to recover from what she put me through.