I don't have any great advice/particular expertise to lend, except that you should probably quit snooping, at least for the time being, because whatever you find is just going to make you nuts. Maybe if/when she makes a concrete commitment to giving the M another shot, that would be the time to insist on no OM contact and absolute transparancy. Right now she hasn't really promised you anything, and if you push her too hard she might bolt. For your own safety you should certainly insist that she can't be intimate with both you and OM at the same time, though.
