Just a thought for you, don't feel like you have to over analyze every word in your response to your T. I always overthink emails and it takes me a long time to get it "just right" even if it's only a sentence or two.

You could say something simple like, "Hi T, Thanks for checking in. I'd like to wait a few more weeks before going back to therapy. I'll let you know when I'm ready."

That's all she really needs to not think that you're quitting forever. You have the choice to go back whenever you'd like but from what you're saying it sounds like you do think you want to go back or think it would be a good idea someday. Again, do it at your own pace but just be mindful of getting comfortable where you're at and like others have said, why you don't want to go.