My T hasn't said it, but I did say it to him...I know that's why I was struggling with everything at the beginning. As well as it being re-traumatising, it can also be an opportunity to heal from the childhood abuse we endured. Triggers can be useful because they show us where we are still wounded, and we can direct our attention there and heal..with proper support.
If my T hadn't seen me in person through all this, I have no idea how I would have managed.