Hello cdg,
The first step is often awareness. Your sub-conscious mind is trying to bring this issue to your attention, for processing. Expressing this issue on here and with your therapist is the next step.......it seems like you are doing this, so well done. I don't know what the best way to deal with this is, because this will differ from person to person and also with the different stages of the healing process that you are at.
Processing the traumatic attachments that lead to hyperarousal can be done by many means. Personally I found talk therapy combined with EMDR to help greatly but I found it great to add in some sensorimotor psychotherapy exercises to help with the physical responses, this helped calm my hyper-arousal and bring more awareness to my sensorimotor and somatic responses.
Then after time, using frequent mindfulness meditation techniques helped to calm my hyper-arousal greatly. I tend to work daily with the mindfulness and this has given me much more self-empowerment and assisted me in my ability to manage my responses to triggers. After being triggered, I would often remind my internal family system that we are here and now rather than in the past, choosing to do extra work also on the parts of my body that were most active during hyper-arousal also helps and ties in with sensorimotor psychotherapy. There are many methods of change, but I can say that these combined responses to hyper-arousal have assisted greatly.
I hope that this helps and makes sense. Best wishes upon your journey.