I always leave the radio on for mine. Right before I leave I give him two treats, he barely notices that I left because he's so busy eating the treats
you can also leave a Kong with peanut butter to keep her busy for awhile. Don't make a big fuss about leaving or coming back, it would cause separation anxiety.
Also if you can go home during your lunch break, it would be great. I think it helps break their day being alone.
But i know the feeling, I think a lot about my baby when I am not home
