Is she crate trained? If she is, I would start crating her and walking out of the room and then walking right back in. Take things in baby steps. Once she handles that, then wait a few seconds in the other room before returning. Like anything else, keep her under her threshold. Nothing is learned when a dog is in a frantic frame of mind. Give her a treat of high value in the crate just before you lock her in. Make sure it is long lasting. When you return, make a beeline for her treat and take it off of her. She will start hoping you stay away a little longer so she can enjoy the treat for a longer period of time. Do everything in baby steps.
If you need equipment to maintain control of your dog, understand you’re hanging on to your dog’s body because you’ve lost his mind!