The One Challenge Standing Between You And Total Happiness

"You think the easiest thing in the world is to be yourself... It's the great challenge of our lives," says Gretchen Rubin of "The Happiness Project."

"I want to be happy. Truly happy."

If you ask most people what they want out of life, that will be the answer. Many of us are eager to find happiness, increase our happiness or hold on longer to happiness, but we have trouble defining exactly what "happiness" looks like and, therefore, how to get there. Author Gretchen Rubin was in the exact same boat -- until she decided to devote a year of her life to find out what happiness is really all about.

Gretchen's "Happiness Project" wasn't a radical pursuit. She didn't embark on a foreign adventure, she didn't give up technology, she didn't take a vow of silence, she didn't try any crazy new stunts. She simply focused on making small, manageable, concrete shifts in her everyday life. These specific acts became a part of Gretchen's personal 12 Commandments of Happiness, the overarching principles by which she could live a happier life.

As Gretchen tells Oprah in an interview for "SuperSoul Sunday," the entire experience led her to realize that her very first commandment was the key to unlocking true happiness: Be yourself, or, as she wrote it, "Be Gretchen."

"That's the most important one, by far," Gretchen says. "But everybody has to substitute their own name."

It might seem like a simple commandment to follow, but Gretchen quickly learned that's not the case.

"You think, 'Well, the easiest thing in the world is to be yourself. You just hang out with yourself all day.' But, really, the more I thought about this, the more I realized it's the great challenge of our lives," she says.

The reason being yourself can be challenging, Gretchen explains, is because so many of us hold onto romanticized versions of ourselves, saying and doing things that we hope can make us seem more well-rounded, more interesting, more enlightened. Gretchen was no different.

"There [were] a lot of ways that I was sort of pretending to be different from what I was -- like music. I wish I loved music. Other people love music; I get why people love music. I don't really love music so much," she admits. "I had this fantasy that I could make myself love music and then I'd be a better person."

Whether it's appreciating music, traveling, cooking, reading, dancing or anything else you feel as if you "should" enjoy, you must first acknowledge the interests that genuinely don't appeal to you. Then, let them go -- not only is it OK, but it opens up more space in your world for the things that truly do make you happy.

"When I gave up the fantasy of this 'other Gretchen' who loved music, then I had more time for the things that I love," Gretchen says.

Only then can true happiness be welcomed into your life.

"The only way you can build a happy life is from a foundation of my own nature, my own values, my own interests," Gretchen says.

Gretchen's full interview airs this weekend on "SuperSoul Sunday," on Sunday, Nov. 8, at 7 p.m. ET on OWN.

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