You are fine. Most people have to work in order to afford the dog lol, so while we all would probably prefer to spend 24/7 with our pups, most of us don't have the luxury.
Most dogs adapt well. If you are taking proper care of her otherwise (when you get home, on weekends, etc) I am sure she is fairing fine.
I try not to leave Jackson for more than 6 hours but sometimes life happens and he does fine. I am lucky I get to bring him to work with me at a doggie daycare some days but he does fine on the days he does not go.