I have to work from 8 until 4:00pm everyday and DH doesn't get home most days until 5ish. My Jada did fine by herself but we felt guilty so we got her a playmate our little boy Bogie. They play good together, but in all fairness I think they sleep all day even having each other. They are pee pad trained so we don't have to worry about them having to hold it for long periods of time. They are super excited to see us when we get home. And they get my undivided attention from 5pm until bedtime,plus they don't have seperation anxiety either. I would say you baby will be fine if you go back to work.
Also I wouldn't want to leave them in a small crate all day. Mine confined to the kitchen/dining area when we are not home.