I'll make one other observation that may prove helpful, if you don't already hate me for suggesting that you're afraid of your horse lol. XD and that is, try standing behind her elbow with a longer rope so that she can move her head all the way around in both directions. With the hand that's not holding the whip, use it to pet her continuously as you swing your whip in the other hand. This will help to truly calm her about the whip instead of merely teaching her to freeze and 'go inside herself' when she's afraid. Does that make sense? If she moves, walk toward her hindquarters rather than standing in front of her and backing her up. By allowing her to move naturally in this way she'll actually release that tension that she's holding in her body instead of stifling it and stuffing it down as happens when she's made to stand still and just 'tolerate' the scary things being done TO her. I don't think so much of making a horse stand as allowing them to stand when they want to and move when they need to. I really don't care if they stand or not, because getting used to the whip while their feet are moving is equally valuable in terms of training.
By maintaining your position behind her elbow instead of in front of the shoulder, she won't be able to run you over and you'll be able to maintain your position relative to hers with minimal effort and risk of being stepped on.
Alright, I'd better stop before this gets any longer.
I agree whole heartedly with most of what Ian said, and in particular with the bolded part. I am not a big fan of CA, or at least the way he is interpretted by many. The part about snapping whips all around the horse and insisting that it stand still and "take it" is not necessarily as valuable in terms of preperation for the horse as training it to be calm around stimulae, even while moving. A lot of horses will just stuff it down, and stuff it down, and when something happens out there that is more than they can deal with, they are trained to stand still and deal with it, but the fear level is so high they just can't, then , they EXPLODE! Your mare might be such a horse.
She is certainly tense throughout the entire training period and when she stands still, you never got any real change in her; she was just as tense and worried as when moving, but she has accepted that you ahve her face clutched up tight, so she freezes , but all tense inside.
Your object in desensitizing is to get a real change in the attitude of the hrose, which is evident in their breathing , their posture and the ovbious muscle tension in their jaw and neck , amoung other things. If you don't see a change for the better, then no mental change has occured in your mare.
I would first of all get a longer leadline, and a heavier one, made especially for ground work. Get at least a 12 foot line. Not 22, but 15 is ok. Heavier rope makes for better feel when sending energy down the line. This will help you.
Give her a LOT more rope in all your dealings with her. If you are trying to teach her, she has to be allowed to make mistakes, be corrected , and allowed to try again until she makes the right choice ( and then rewarded. And I agree with the others in that you need to be looking for many opportunities to give small rewards and BREATHE!). But , if you are holding her head up so close, she cannot really make any choice. It isn't allowed. So, all she learns is passive helplessness.
I think it's very brave of you to show this video and I am guessing that you are trying to teach yourself all this on your own, no? It would be so nice if you could get someone like a mentor to help you.
I know this is way out there, but one of our member, Cherie, lives in Oklahoma. She is a lifetime horsewoman and might be willing to help you if you asked her . You could make some real changes in your skill and take that lovely mare along with you. Best of luck.