Wow, thank you all for the replies. I helps a lot to read other points of view.
And it all makes a lot of sense.

It definitely is great that someone doesn't freak out, doesn't send me away... Especially when it's a T who helped me so very much in the past. When I only had the thoughts and never experienced making real plans, this would have been what I wished for.
Now it feels as if I became too afraid of myself and my thoughts turning into plans. As if I'd like for someone to 'get it' and shake me. Although I do know it's good that my T is still there, not sending me somewhere else and helps me to get through this in her own kind of way.

I'm almost sure it will pass without any harm, guess she does too and trusts me with that. But I think I'll eventually talk about what I wrote here. It's indeed very important to feel understood by your T and I'm not sure whether that's the case right now... even though I can see logical explanations for the behavior. I'm probably not the most logical thinking person at the moment though.