In your window as a stand-up sign. Painted on a dressing room wall. Or even made into staff T-shirts for your consignment shop (for a "Superbowl Sunday Widows" event? Your husband called and said to buy anything you want.
A single glass of alcohol doesn't make someone an alcoholic, and an occasional "retail therapy treat" hardly means you're a shopaholic. But if you do it regularly, you just might need to pay attention.