Dog Tearing Up Bed

I have a 4 yr old Italian Greyhoud that has starting tearing up his bed. He was given to me by my son since he was going overseas and could not take his dog. About 6 months after he came to live with me he started tearing up his bed. I mended the bed a few times and then had to buy another one. For a few months he was fine with the new bed but then started tearing up that bed. It usually happens when he's in his crate when I 'm at work but recently he started tearing it up at night too. Can anyone offer reasons and/or solutions to this? Today the dog is on towels in his crate while I'm working.He does not tear up or get into anything while I'm home and he's out of the crate. I'd like to buy him another bed but wonder if that would be wise. Thank you for any help or ideas.

He sounds frustrated and upset. After all, he's lost his home and owner - basically his whole world.

How much time per day is he spending in a crate and how much exercise is he getting?