For years, novelist Richard Paul Evans and his wife Keri struggled with their marriage. Then, one day, they learned to ask each other a simple question: “How can I make your day better?”

The question, which Evans wrote about in a viral blog post, saved their marriage.

The Salt Lake City, Utah couple said their vows when they were 21 years old. They had unreal expectations about love, says Evans. He says their relationship soon unraveled over petty power struggles. Years later, it had gotten to the point where they barely acknowledged each other, he says.

“I loved her, I knew I loved her, she loved me,” Evans tells NBC BETTER. “We just didn’t know how to make it work.”

Then, one day while taking a shower, Evans broke down and cried. He had an epiphany: He couldn’t change his wife, but he could change. The next morning he asked his wife a simple question: “How can I make your day better?”

“It was a matter of humility,” says the 55-year-old. “It was a matter of saying ‘OK, I will do whatever it takes to make this work.’”

At first, he says, his wife was hesitant to believe he was sincere, so she tested him. She told him to clean the kitchen, which he did. The next morning, he asked her the question again: “How can I make your day better?”

“Clean the garage,” she responded.

Though it would be a big job and he had a busy day ahead, he did as she asked. The following day, he asked her again: “How can I make your day better?.” This time, she told him there was nothing he could do. But Evans persisted. He asked her every morning for two weeks: “How can I make your day better?” Finally, he says, his wife broke down.

“I should be asking you that,” she told him. She apologized, and said, “Can we maybe just spend time together?”

Now, every morning, the couple ask each other how they can make each other’s day better, says Evans. It has “absolutely” improved their relationship, he adds. While it may seem simple, asking your partner this question is probably difficult if you aren’t getting along. Here’s how to do it the right way, according to Evans.

Accept that your partner isn’t the only one to blame

The first step to healing your relationship, says Evans, is accepting that you are as much, if not more, to blame.

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“I’m not as great a guy as I thought I was,” says Evans. “I have a lot of really broken parts, a lot of baggage I brought to this. And I was thinking this was her, and the truth is, I suck a lot.”

It can be hard to accept blame, says Evans. But once you do, it can be liberating, he says.

“We all have unlovable parts, we all have demands that are unreasonable, we all have parts of us that are unacceptable,” says Evans. “And to finally get to that state and accept it, and accept that we’re broken, is a beautiful, liberating thing to say, ‘OK, but love can win, I care about you, and I can respect you, and I can do better.’ It’s a powerful place to be.”

Be sincere

When you ask your partner what you can do for them, you must be sincere, says Evans.

“This is not a psychological manipulation, this is the real thing,” he says. “You’re saying ‘OK, I’m putting it out there. I’m willing to suffer for this relationship. I’m willing to suffer your bad parts to help my bad parts, and I have faith in you.’”

You have to be willing to go “the whole way,” he explains, otherwise, your partner will never trust you.

“As soon as the trust was there, she realized, ‘He really likes me. He’s getting nothing out of this. He really wants this. There’s no ulterior motive, he’s trying to save our marriage, he’s trying to show me he loves me, he cares about me, he’s taking care of me,’” Evans explains.

Many people in relationships focus on what their partner should be doing for them, when they should really be focused on what they can do for their partner.

It’s about the nature of true love

Many people in relationships focus on what their partner should be doing for them, when they should really be focused on what they can do for their partner, explains Evans.

“It’s not about what you can do for me — that’s not a question,” he says.

He pointed to a popular Italian expression: “Ti voglio bene.” The phrase can be interpreted as “I love you,” Evans says, but more specifically, it translates to “I want good for you.”

“I think it is a wonderful explanation of love,” says Evans. “It’s not a matter of saying ‘What can I get out of you?’ It’s saying ‘What can I do to make good things happen in your life?’”

Evans and his wife now enjoy a remarkable marriage, he says.

“Having someone who I adore and who I care about and who I know has my back is a remarkable, not just asset, but treasure in my life to have that,” says Evans. “Many, many people don’t have that, and to have someone that close — that’s something that’s worth working for.”

How to ask your partner “What can I do to make your day better?”

Accept that you're at least partly to blame: You might be tempted to see your partner as the problem. But you must accept that you are likely also to blame.

Speak from the heart: Asking your partner how you can make their day better is not about manipulating them. When you ask the question, you must genuinely be willing to make them happy.

Realize what 'true love' really means: True love is not about what your partner can do for you: it’s about what you can do for your partner.

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