Hello Z-man,
dealing with push-pull is hard and exhausting . You are paying the price for problems that are not yours at all. Take good care of yourself - see this as a break you use to recover. I'm not saying all will be fine and she will return - nobody knows - but right now see this as recovery time you use to the best of your advantage. Chances are if you are doing better the relationship will do better... .
There is little advice possible in the sense of do this then that will happen. However the LESSONS provide you with a path to acquire skills that consistently applied tend to nudge situations into a healthier direction. BPD by definition is so volatile that any specific interaction often can go in any direction. That makes it so disorienting. With the right skills you can see the patterns behind the behavior, can react appropriately in a situation and that often makes all the difference.

,
a0