It seems like the issue with the fish has brought up deeper feelings of insecurity and doubt in your relationship with Dr. T. To me it’s just about wanting to be a part of his space and to be thought of even if you weren’t there.
Your efforts to assert yourself and express your needs are important steps.
The robotic reassurance may reflect Dr. T's own discomfort with emotional expression or a defensive response to feeling challenged.
Could you explore this with R? It's also important to consider your own boundaries and needs in the therapeutic relationship.