Can you trust her?
This is the flip side of the jealousy test. Have one of your friends or a business associate hit on her and see how she reacts. If she opens the door and invites him in, it means she's still on the lookout for the BBD (Bigger, Better Deal), and it's just a matter of time before you're out on the street.
Me, me, me
Today many, many women are selfish, self-obsessed narcissists who expect men to coddle them and cater to their every whim. This is because they hold the sex trump card and know it. To test her selfishness quotient, insist (over her demands) on eating at a restaurant you pick, or opt to stay in and watch a DVD instead of going out. If she's a spoiled brat who only cares about herself, you'll find out right away.
What does she really want?
If you're a good-looking guy, it's possible that your girlfriend is only interested in your looks. To test her, show up for a date sprouting stubble and wearing your rumpled old clothes from high school, or pass on taking a shower after working out. If she thinks it's "cute," or reacts with a smile, she passes with flying colors; but if she throws a tantrum and starts screaming about how embarrassing it would be to be seen with you, it's time to move on.
If you're a guy with lots of cash, it may just be that she's angling to wrap her sticky little fingers around your wallet. To deal with her, tell her that you're about to lose your job, so money's tight. Or pretend that you forgot your wallet and that she'll have to foot the bill. Or even start a discussion about the necessity of prenuptial contracts. If this earns you a flat, "I can't believe this" stare or she starts calling you "cheap," head for the nearest exit.