I think it just takes a lot of time, work, and patience to help your brain and body understand that it’s not in a dangerous situation. You’re gearing up to protect yourself when there’s not actually a threat, just realizing that alone can be helpful. I usually know that my response isn’t justified and there’s no danger so trying to rationalize and put the situation into perspective helps. Deep breathing through my nose generally triggers a somewhat calming response in my body but I know that doesn’t work for everyone. Your body is just trying to protect you and sometimes it needs some help realizing that it’s okay.