Many things are rationalized in therapy as "normal" but I think the way therapists intrude on people's consciousness is creepy. It's not the fault of the client, it's the nature of therapy. I cant imagine what good could come from this scenario. Therapists would preach about it being an opportunity to understand some maternal "transference" issue but seems more likely it's an artefact of therapy weirdness, and regardless I'd consider "working thru" such a thing to be a colossal waste of time, and might open a messy can of worms.