My mother owns a poodle that suffers extreme separation anxiety. She bought him as a young adult (2 years) from a breeder, she has had him for 18 months and has two other dogs. He has always been clingy, but it progressed to an untenable point within the first six months of her owning him.
He cannot be left alone, ever. He has damaged the house, he has actually dug holes through doors with his claws trying to get out and follow the last person to leave the house. So they are forced to take him everywhere they go or leave someone at home. This has been going on for a year.
She'd rather not sedate him, what can be done to help a dog with such severe separation anxiety?