((((Purple Heart))))
Yes, grounding techniques are necessary in those times. I find myself looking away (from the trigger) and looking at wherever I am, trying to tell myself that I'm NOT there. It's over. I am okay. Sometimes, that reassurance only lasts a couple of moments and I "fall back" again. It's weird and very scary!
I do take medications, which do help a lot with preventing flashbacks (somehow). Very gentle hugs to you.