I find my self flinching also as I get older.
Its really bad shooting handguns with my left hand and shooting flintlocks.
I can dry fire no problem but I really need to concentrate when live firing. I can always tell with my revolvers on the empty chamber. Drops low and right
Dry firing helped me improve my shooting, too. I would put a coin on the barrel and pull the trigger without making it fall. It sounds easy but doing it over and over changed the way I reacted.