The reason they are scared is because they are afraid that they are losing what they worked so hard for. There is some shame, which is why they say "how could i do this to someone that i love". That's to protect them from the consequences of their actions.
My WW was emotionally and physically abused and assaulted, as well as sexually assaulted before i met her. She has never dealt with these issues. I pick up on this forum that alot of the WW's and WAH's have all bottled their emotions. They only know how to run.
You need to get her to face her reality, which can be so difficult if they've moved out already. All that you can do is detach and hope that she comes back to you.
Just cos things are going right, doesn't mean that they were always wrong.