Crate Training for adult, blind dog

Our 13-year old Brittany has been blind for about 2 years. He has always been anxious, but now he is super anxious especially when left home alone. We had attempted to crate train him when he was a puppy but he seemed to hate it from day one--I'm talking chewing the crate, lunging himself against the bars, getting his snout stuck between the metal slats....it was horrible and I thought he was going to harm himself. We tried a small crate and a big crate and then gave up. Fast forward a decade, and the second we leave the house he paces and paces, hyperventilating trying to find us. We don't leave him for long periods of time, but 1 hour seems like 10 hours to him. He gets 20 mg daily fluoxetine and we have tried Xanax, CBD with some THC, and pain relievers but nothing settles him down. I am thinking now to retry crate training, so he won't feel compelled to walk around trying to find us. Any thoughts??