I don't know if it's a rupture or not......but probably a reaction to letting the emotions/the intensity of them out, a sort of stepping back, a detachment. They feel different confessed than they did unconfessed.....if that makes any sense! Now that you have talked about those feelings, they are mutually known between you, it can't help but affect/change the dynamic in your relationship.....or even actually change how you do feel/think about her.
I don't know.....I'm having some difficulties/confusion with how I'm feeling about my T and the dynamic of our relationship, too. For a while, I felt what seemed to be like a secure sort of attachment to me, strong but not too intense, then it seemed to be overwhelmingly powerful and intense.......but with the various discussions we've had about limit-testing, boundaries, authority, etc., it feels like something has changed too. But actually, I know that she re-defined the boundaries, strengthened them. It feels like she has withdrawn from me, too (like choosing not to sit closer to me yesterday when she generally does; I said I noticed that, she said she had decided she preferred that chair really, she was going to stay there from now on and if I wanted to be closer I was welcome to sit closer to her).....and somehow, it's making me feel more distant from her, withdrawn in a way from my attachment, too. Like when you say you wouldn't mind never seeing her again....I think I am beginning to relate more, and it's bewildering to me to feel this way when I've always looked forward to seeing her and felt very positively about her. But I've been thinking the last couple days I'd like to run away, never see her or think of her again, like maybe I don't really love her, just that I thought I did for whatever reason!
....it's not so much being numb as maybe simply having grown weary with having to deal with the pain of attachment or the drama of relationship dynamics and wondering if it's really worth it to continue. I imagine if I tell her these things, she will likely say the feelings are probably pretty normal, a part of the flux that can be in a therapeutic relationship.....people's feelings/emotions/perspectives are in a state of flux, not static but dynamic, and so relationships reflect this. And maybe the T relationship exaggerates it..... all this thinking about this makes me feel like this >
Anyway, maybe it's a phase that will pass if we don't react too dramatically to it!
And probably it's worth mentioning to T, because it is something to explore.....

Oh, I don't know how much help my muddled meandering is to you.....