Thank you so much for posting about this PG

Especially the part about not discarding it all together. I have the opposite struggle in some ways- not having enough armour to protect me from the hurts of the world, and I often fantasize about being able to build myself a set of armour so complete that noone could touch me. So thank you for describing the middle path- having a reasonable set of armour, and making wise decisions about when to wear it and when to lay it down.
Two random ideas came to mind while reading this thread. One is that it has sometimes helped me to externalize/anthropomorphize/physically create whatever the 'it' is that I am talking about. I wondered, for example, whether you could make yourself an actual shield (cardboard, tin foil... really!) and experiment with how it feels to lay it down in front of T. And picking it up again when you feel the need. Things like this helped me to notice much more closely what was happening for me.
I also liked the part about trying to use more feelings words. I can relate to finding it so much easier to think than to feel. One DBT challenge I found helpful was to stop every time I heard myself saying 'I feel' and check that it really was followed by a feeling, rather than a thought. Hope that makes sense!
Sounds like you and T are doing such good work together