She's just a girlfriend, and you have to hide receipts from her? Keep in mind, things get much worse when you're married - she'll own your every move! My philosophy is to keep the spending in the wide open when dating. Then pick the girlfriend who doesn't seem too bothered by it. Even though it's guaranteed to change when you marry, at least it won't be to the level of the one's who want to control you even before you're hitched.