EEman,
I am sorry about your issue. Unfortunately things like this are becoming more common. Since I am very busy, my wife goes online at least three times a week and checks for strange looking charges.(So much for my impulse buying habits.) I always get asked "What is this for?" We have actually isolated real charge mistakes and have corrected them immediately-to say nothing of my getting caught with my "as seen on TV" weakness.
One other thing to consider: Some companies offer a" virtual credit card" system. We have a Citibank Visa card and are enrolled in this program. When we buy something online they generate a one- use credit card number that is linked to our card. If someone tries to use that unique number a second time it is invalid. It works great and provides us piece of mind. You might want to look into this with your credit card company.
Peter