My wife did the same thing a few months ago. I 180'd the instance she dropped the bomb so she stayed for 2 months and and she saw massive and profound changes in me (for me i might add). She still left.
Once they are going that's it. They HAVE to leave. It's what happens then that is the the question. My wife is 1 km away and we have alot of contact.
Defineately do not persue in her any way. Try for an autopsy of what went wrong in the relationship. Try and support her. Try and be up beat.
