What you are going through/feeling is extremely normal. I can remember wanting to ML ALL the time. Part of it I think was to 'restamp' my mark/scent on my H and part was to make sure he didn't have the energy to try and ML to OW if she did happen to make a play for my H again.
Does OW hold a position of much authority in your H's practice? Do you think there's a chance that because of your H's decision she may find it hard to continue to work there and might look elsewhere. OW in my sitchcouldn't face the other staff in my H's firm after he dropped her: she felt she had lost all credibility and I don't think she could take being seen as having 'lost'.
I think it's a good thing to subtly re establish your turf.
This time is hard and things will fluctuate back and forth emotionally. Just keep on with your being there and making your H feel safe and secure. Make this a great Christmas
Saffie me 46 H 46 M in 1986 D20,D18,S16,D13 H's A 01/05 to 07/06 H recommitted to M 07/06 renewed vows 09/06 Going from strength to strength