Mark,
You’ve had great advice so far, particularly praying the prayer to St. Michael the archangel, and asking the Holy Spirit to guide you through these interactions, and to reveal what course of action He would like you to take.
In similar situations, I have found myself getting angry out of hurt with close friends. Ultimately I have taken this anger to confession . Granted it was reasonable that I get angry at this situation, but did this anger drive a wedge between me and the Holy Spirit? (absolutely yes!)
You may not be able to affect this persons actions, and the best course of action may be to avoid them. But if that is impossible, keep focusing on your own reactions, and how they conform to or distance yourself from the Image of Christ which you would like to conform yourself to.
Just today, I wound up having a conversation with myself, replaying the way in which this certain person had hurt me, and all the ways which I could (charitably
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) inform that person just how much they had hurt me. And I felt so righteous in each of these imaginary conversations. Because I was the victim, by golly.
Well, it got out of hand and I was just getting angrier and I finally appealed to St. Michael and decided to go to confession, and the anger finally melted away. Is that person still wrong? Yes, but I can’t control that. I can control what I allow them to do to me.
my very small 2 cents.