1. You tell him things you don't tell anyone else. We don't mean blurting something out after you've had too much merlot, but the desire to tell him intimate details about your life means you trust him—a major component of successful long-term love.
2. You let her see you in moments of weakness. It's easy to be happy with someone when you're feeling good about life. But what about when you're not doing so well? Do you want to see her when you've been denied a raise, or your cat died or you had a plain old bad day? She should be a comfort during tough times, not a burden.
3. You respect him. You don't want to change the essence of who he is. There may be stuff that irritates you in everyday life—he insists on wearing his favorites, holey T-shirt, he eats sugar cereal for dinner, he still watches Saturday morning cartoons—but you like him, plain and simple.
4. You want him to meet your parents. You feel proud of him and you want to show him off—as opposed to feeling like you have to make excuses for him.
5. You can imagine a future together. You don't have to practice writing your first name with his last name, but do you periodically let your mind wander to picture a life together? Is it amazing?
6. You're not afraid to disagree with him. You know that even if you fight, he'll listen to you and won't brush you off. He takes you seriously, even when he thinks you're wrong.