Then I get a text message from the xOM's XW. She is yet again sending hate-filled messages to me. While I certainly understand that she is in pain, I would like this to stop

change your phone number. she ahs every right to be angry with you... as you have every right to make it impossible for her to contact you. I hope you have previously apologized to her.
I think if I were a WS or FWS and hurt another like this... I would constantly sleep with one eye open and watch my back.
But... changing your number is the way to handle this... the OM should not have a way to contact you either... so all phone numbers and email accounts should be changed.