Her response is indeed very strange but at the same time, were you really prepared for a "no" response? My therapist has never and would never say she misses me and the reason is because she does NOT miss me. She told me this in so many words. Perhaps your therapist didn't want to lie. I know it sucks but it's the reality. Of course you were looking for reassurance and that's perfectly normal but clearly this was a boundary crossing for your therapist. Hope your surgery goes well.