I like your quote about the fruit and the tree. 
I should take back what I said about the sympathetic nervous system being difficult to override. It can be done pretty easily, but if it's in the habit of being vigilant, it's difficult to keep it from doing what it always does as soon as you stop attending to it. Breathing, meditating, using visualizations, self-talk, journeying, all that stuff can be really effective too! It's any of that stuff that gets us out of the problematic (primarily western) way of thinking that our bodies are just tools to carry around our heads!
It's good to acknowledge the trauma with one who has had a similar experience! I wonder if any part of the trauma is affected by the care and respect (or lack thereof) shown to a person when they're in that vulnerable state? Part of the trauma experience is a lack of being able to escape a situation deemed unsafe, so...if those who are handling our bodies/surgeries make sure to keep us feeling as safe as possible, could that produce better results? I dunno!
Best to you, too!