hi sarafina,
I bet the people here will understand. Welcome. I hope you post more.
In my case, the BPD'd people in my life are my Mom and step daughter. I believe they are both probably NPD'd too. Jury's still out on that one, but a common thing that occurs with the narcissist (I think) is they can smooze people and are very selective who they target. So you get a lot of gaslighting as a result.
Thus, the "your Mom is always nice to me" I often get. grrrrrrrrrrr
It was very validating when my Mom's best friend for most of last decade contacted me on Facebook (this was about 10 years ago), after they had a falling out, to let me know she always thought I was a nice person and didn't understand why my Mom said such horrible things about me. So. Maybe if you wait awhile, the tides will change.

b