The longest I've been gone is around 10 days. My greys were fine, happy to see me. My mutt wouldn't even look at me for a week ! She is worse than a human. I never kenneled them again, now we have a petsitter come to the house.
Bella has no desire to run. We now have a large fenced in yard and she goes out and lays down ! She hates to go for walks too.
She is the laziest greyhound I have ever owned !