No I don't have kids, and convinced now that she is having an affair, booked a one way flight back home for her and she has agreed to go.
I believe she has already found her rebound guy, thank the Lord.
Sorry that you are going through this. Sounds like you might already have an out. Perhaps to cement things you could try to be undesirable, like by letting yourself go a bit (like spill some spaghetti sauce on your shirt while eating and then just let the stain sit there while you watch TV -- but don't make this too obvious that it's intentional). Just whatever you do, be careful. These folks are dangerous, especially so during the departing phase, even if the departure is 100% on the pwBPD.
How long were you married? At what point did you discover the concept of BPD?
Also, I would try to secure any valuables, tangible or intangible, as these folks seem to not mind taking a scorched-earth, ransack-for-all-I-can-get approach.