I am gone from home about the same amount hours you are so Brandi is home alone during that time. However, I work from home every wednesday so she's only alone at the most two days in a row. Brandi does fine on the days she is alone. She sleeps most of the day in her ex-pen. I have water, pee-pads and her bed in there. I also have webcam setup so I can check in on her.
To be honest I think she likes it when I am gone because she can sleep undisturbed for the whole time
. When I work from home, I am constantly waking her up so I can play with her, or walk her so she doesn't really get any sleep when I am home all day...more like cat naps. My Brandi can sleep 20 hours but then again she is a lot more older.