If you're wondering how to hurt a fake friend, the answer is simple: by being yourself. A fake friend is someone who only wants to be around when it's convenient for them, and they don't really care about your wellbeing. So, if you're feeling like you need to put on a persona around this person, it's likely that they're not really your friend. Just be yourself and let them see that you don't need their approval or validation to feel good about yourself. If they can't handle that, then they're not worth your time and energy.