When my friend Greta got engaged many years ago, a man she knew from work shared a story I’ll always remember.

In essence, he told Greta the key to marriage is to love your spouse even when you don’t feel like it. Using his own life to explain, he described a period in which he and his wife hit a wall. They were fighting constantly and very disconnected. Their marriage hung by a thread.

Her birthday was coming up, and though he wasn’t in the mood to act kindly, he planned a surprise party. He forced himself to show love he did not feel, and it took every bone in his body to follow through.

As you can imagine, a surprise party was the last gift his wife expected. When she walked in the room and saw what he’d done, she looked at him dumbfounded. She’d been thrown for a major loop.

This man went on to tell Greta how the party turned his marriage around. By treating his wife differently, she treated him differently in return, and with every inch one of them gave, the other gave an inch back. Before long they set in motion a new dynamic that helped rebuild their marriage, which became stronger than before.

No matter how happily married you are, or whether you’ve experienced your own rough patch, I’m sure you can relate to this story. Every relationship has ups and downs, and when you consider all the things married couples share—money, bills, kids, duties, decisions, a bed and a bedroom—it becomes clear how much room there is for big-time conflict.

Even the best marriages have healthy debates, and while bumps in the road are normal, trouble can arise when unresolved issues dig under our skin and fester. Over time, they can do real damage.

Marriage takes effort, but just as important as effort is a long-term commitment to each other. When we meet our soul mate, it’s all passion and fireworks. Our emotions take over, creating an intoxicating high. We start riding on cloud nine, a fanciful place we never want to leave.

But sooner or later reality kicks in, and as we gravitate down to earth we realize that passion and fireworks can ignite love, but they can’t sustain it. What starts as an emotion becomes a decision because we can’t always rely on our feelings. Some days we don’t feel like loving our spouse. Some days we feel like wringing their neck, or shaking sense into them, and they feel like doing the same thing back.

This is where love becomes a choice. This is where we put our head over our heart and choose to love our spouse, hoping our emotions might follow. As C.S. Lewis said, “Love is not affectionate feeling, but a steady wish for the loved person’s ultimate good as far as it can be obtained.”