I think I've experienced something similar, rainbow, though not recently. In the past, when I felt cared about by my therapist, I would feel physically aroused. It literally did feel as if my wires were crossed. It didn't make any sense to me at the time, and I definitely felt weird. I never got the chance to talk about it, though, because I was too confused and fearful of being shamed for it (and I'm not working with that therapist anymore). I'm still not quite sure what to make of it.

I hope you do get a chance to talk what you're experiencing through with your therapist. Given what you've said about her, my guess is that she would receive whatever you have to say with grace. Hope it goes well.