I wonder if there's a way that you can just block your T on facebook, so that any of her posts on your friends wall won't show up for you? I sort of ran into the same situation because a woman I went to school with is friends with one of my old T's on facebook, and I clicked on my old T's profile and blocked her, and when I click on my friend's friend list, my old T's name doesn't show up anymore. So that might be something to consider.