Hi,
Such an interesting discussion!
I think that everyone, both therapist and client, have all sorts of different boundaries around how close the therapy relationship should be in terms of how each expresses caring and that's just fine!
I personally value this type of connection, (I call it love, but I'm sure it can have whatever name you want) so much. I'm so relieved when I can safely express the strength of the love I feel for the therapists I've worked with, and yes this develops over time.
I don't think I'd feel comfortable with someone who would back away from me or say that they'd never say they love me back. I believe if the connection is right, both people are really in it together sharing themselves and who they each are in ways as the therapy develops, and can both come to really care about one another in a very personal way, while still respecting that this is a profesional relationship.
I feel this way about my voice movement therapist. We've worked through many issues both within our relationship and around my understanding the very unique creative work that she does. She's been incredibly consistent and deeply caring no matter what. She's gone out of her way to gain my trust and really get to get to know me and the very best way to relate to me. I don't have any question about how much she cares about me. She knows how much I care about her too, and says she's deeply touched.