I know I have that in me as well but it hasn't acted out in a long time. It does get better with age. It takes a lot rewiring like you are doing. I have to do that with my trigger for abuse, and loud sudden noises. Haven't been abused since I was 18 but my heart still pounds while I am talking myself down. You are on the right track. Maybe be more mindful of it while it is not happening and make a plan to do some distraction when it does occur next.