While i agree that if she went ahead w OM i would probably file D but i like doodlers suggestion.

Convey your concerns about other OM and her behavior and that it would legitimately get in the way of you two ever reconciling. She can either choose you or OM without you having to give ultimatum or threats of D.

Me31 W31 M11yrs S6yrs
23Mar16-BD
9Apr16-W admitted EA w boss.
27Jun16-W Changed job and promised NC w OM.
14Jul16-Continued contact w OM.Start of Separation.
24May17-Divorced.