This may seem like a “duh” moment (Yes, I’m an 80’s child, deal with it.) but never share your credit card or bank account with someone, even if they are your boyfriend. Or girlfriend. Even if you’re buying a house together, don’t enter into any financial scheme until you have a good idea of how the other person handles money. If they never pay their bills on time and are always behind and scrambling for money, they’re less likely to pay YOU back. If their name is not on the credit card they are not going to feel obligated to pay any of it off even if they helped rack it up. This isn’t selfish, it’s just smart.