Ha - I used to do that too. I was in South Africa a lot, 2 weeks at a time. I used to shave before I met my wife, but she'd only ever seen it hairy. It was very liberating to shave as I arrived, knowing that in 2 weeks the signs would be gone.
I think the best way would be for her not to see it, but only to feel it. Once in bed, get your sleepware off and bring her hand over for a feel.
Good luck, I can only think she'll be thinking you were with someone else!!