Look. If you say to the therapist you can't make the appointment you are well in your rights to not be pressed on the reasons why.. eg: if she says 'whats up?' You can say with authority* 'I'd rather not go into it right now...lets discuss it at our next meet maybe'..... if she presses you just repeat the sentence. She's being controlling.

Ed: I'd hasten to add 'and an even tone'..you don't need to sound defensive or agitated. Stay calm.

Best wishes