In this forum I often give the benefit of the doubt to the spouse claims that he/she is going out/away with friends. In your case, you're certain she's had an affair with OM1 and OM2 in the past, so I feel less of an instinct to give her the benefit of the doubt, but I do wonder really if this particular trip is innocent.
That's neither here nor there.
I think you do have to decide what your boundaries are. You shouldn't go snooping, but if you become aware that she is continuing with an EA and/or a PA, does that cross a boundary? If so, what will you do to protect your integrity and sanity?
I believe, for myself, that if I became aware of a PA, I would go file the next day. But that's a very personal choice. I know that people do reconcile after affairs.
Me: 50, MLC/WW 45 Young kids Nov 2015: BD1 Apr 2016: BD2 Jan 2017: W filed Feb 2017: D final