Very similar sitch. The RO may have been suggested by OM(cop) as a way to keep you out if the picture while he gets implanted with your W. My W left in November last year and by December was talking divorce. I told her I was against it and she kind of sat on it. In march, she filed, but it was done incorrectly so the state doesn't recognize it. If your desire us to save your marriage, you must slow down the divorce process. There is much guilt and she thinks that by quickly divorcing you, the guilt of being an cheater will go away.
This is going to be a painful time because they RO ties your hand. Right now, that is going to frustrate you but you will come to see it as a blessing. You must detach emotionally from her right now to get your bearings and to clearly think about what you want to do.
Because of the RO, there isn't much you can do for your M, so put your focus on you and the kids.
Stay on the boards, there is much help and support here for you.