Have you explicitly told him what kind of behaviours you display when you are triggered? You can't rely on him interpreting your behaviours correctly, especially not at such an early stage.

You obviously remember how you behave at the point of withdrawal, are you aware at the time that you are triggered and/or dissociated? Or are about to enter that state? It took me a long time to be able to do this, but I can now identify when I begin to withdraw and can say something really short and blunt to indicate that I need help to ground. I am also working with a new therapist and it has become very obvious to me that I need to take responsibility for communicating what's going on for me because I can no longer rely on the well established knowledge and experience of me/my process that my ex-therapist had acquired along the way. It's been good progress for me to take responsibility for articulating my stuff - it is a more adult space and I am less reliant on the young parts who need/expect the attunement which they never received (and which it is no longer possible for me to receive, what a world of pain that is). It's not his job to work you out. Maybe this is related to the previous/perceived enablement on which he has commented.