Hi Lostinanother,
My most likely thoughts are that she is in an emotional-slump and needs to reach out for some soothing to get through it.
I agree with
Cromwell, you probably already know that BPD is an attachment disorder a pwBPD doesn't completely detach like you or I. As previously stated there's something going on in her life and she's reaching out for soothing, she may even be trying to create an exit plan with you from her current bf. It doesn't matter what she wants, it matters what you want, give her radio silence and don't give her attention the sooner that this will blow over.