I agree with Salingeresme. Too much intense focus on past traumatic events, without enough resources to cope when the sessions ends, often results in a level of transference, attachment, and neediness that is difficult to cope with.

Since my t is not available for support outside sessions, I cannot allow my therapy work to exceed my own limits of coping. I have had to insist on "stepping back" whenever working on past traumas has left me feeling too anxious, unregulated, and needy for my t.

I noticed that you are relatively new in your therapy with your t. Is it possible that your t is trying to accomplish too much too soon?

It is pretty common to have intense feelings of attachment, anger, anxiety, etc., come up in therapy due to transference. What you are experiencing isn't abnormal. Your t is correct that as time goes on, those intense transference feelings often become milder and more manageable. (It hasn't been very true in my case, but I know it has been true for many others.)