By Doug Lange

When I was courting my wife, I had these vivid images in my mind of a happy and perfect marriage. I knew I was a good person with a friendly, easy-going personality, so naturally, I assumed I was destined for an incredible marriage. I was genuinely shocked, though, when shortly after getting married, I realized that many of the traits I thought would impress my wife were actually the source of challenges between us. It never even crossed my mind that I might one day really bug her.

Marriage is hard. Divorce is at an all-time high, and it almost always comes down to how we behave toward our spouse. The way we think about, feel toward, speak to, and act around our spouse determines the strength—or the weakness—of our marriage. Our thoughts, feelings, and actions are our behaviors, and all behaviors are driven by our beliefs.

By definition, to "believe" means to take something as real or true. Our beliefs continually fuel our behaviors. There is nothing we do that isn’t built on, and preceded by, some kind of belief. What you believe—what you take as real or true—about your spouse or your relationship will determine the happiness and success of your marriage. So ask yourself: what do you take as real or true about your spouse? Think about your spouse's characteristics and personality traits, and complete these sentences: "My spouse is…" or "My relationship with my spouse is…" Write them out. What you come up with is what you believe about your spouse and your marriage. Now look at your list—are your beliefs more positive or negative?

If you’re unhappy in your marriage, it’s a reflection of the beliefs you hold about your marriage. Your marriage is exactly what you believe it to be. You treat your marriage and your spouse in ways that line up perfectly with the beliefs you hold. So if you're not happy, the first step isn’t to change your spouse—it’s to change your own beliefs.

Andy Andrews, author of The Noticer, said, "Happiness is not about circumstances, it is about perspective. And, perspective is a matter of how we choose to see things, and how we see things is a matter of choice." How we choose to see our spouse is exactly that—a choice. What we believe about our spouse shapes what we see. Choosing better beliefs is choosing a better marriage. When you change the lens you’re looking through, you change what you see.

Get clear about what you want your marriage to look like. Create a vivid image of the type of marriage you want. Focus your mind on the outcome, on building a joyful marriage—not on fixing your spouse. Start with your beliefs, and your behaviors will naturally follow. Beliefs first, then behaviors.

If you want a happy marriage, you have to first believe that you can have one—and that it’s worth working for. Create that image in your mind and treat it as if it's already true. A parked car isn’t going anywhere. You have to act today like the marriage you want is already within reach.

Now, I want to be clear: unhappiness in marriage is different when abuse is involved. While I believe abuse stems from distorted beliefs—and that beliefs and behaviors can, in theory, change—no one should stay in an abusive relationship. You have to get out. You deserve to grow, to flourish, and to be happy. No one deserves abuse.

The images you create in your mind about your marriage need to be clear—and you have to hold onto them long enough to actually start believing what you're envisioning. When disagreements happen, pull up that image and act according to it. Don’t react to the moment. Respond according to the marriage you’re choosing to build.

Happiness in marriage is a choice, not a circumstance. And circumstances change when we change what we believe. So the real question is: what do you want to believe about your spouse? The choice is yours.