Dude, your gf must be my ex gf's long lost sister LOL. I know exactly what you are saying. I moved out and away a few months ago. Believe it or not, at times I feel like I miss her and get jealous because she went back to the guy she was with before I met her.
I one day just had enough, I went and bought some boxes and started packing my thing right in front of her. She couldn't hardly take it. By the next day I had all of my stuff out of her house. She called me and asked me to come over later that afternoon. She said she found a few things I forgot. I went over to get them and she tried to lure me back in but I resisted.
I went back a few times stayed a few days at a time but it was more of the same BPD behavior. I finally totally left a month ago almost. They can't help themselves from continuing to try to cause pain for us. My story is under the title "Free from a BPD relationship or not?" Check it out if you want and let me know if I can help you, Bunk