In 2013, Stephanie Harrison's life looked perfect on paper, but she was deeply unhappy behind closed doors.

"Everyone had told me that I was doing all of the right things," Harrison wrote in her book, "New Happy."

"But in reality, I was unbearably lonely. I had daily panic attacks, developed a stress-induced autoimmune disease, and felt an overwhelming sense of hopelessness almost every day."

During one of her saddest moments, Harrison said she developed a sense of curiosity about her unhappiness and felt inspired to find concrete answers about how she, and others, could be happier.

More than 10 years later, Harrison now has a decade of experience studying the science of happiness. CNBC Make It spoke to her about why she challenges the common definition of happiness and offers up a new one.

CNBC Make It: How long have you been researching happiness, and what inspired you to start?

Harrison: I have been studying happiness for 10 years now. And really what inspired me was my own unhappiness. Experiencing my own challenges with my mental health, my physical health, my relational health, and that compelled me to want to understand what I was doing wrong.

But as it turns out, there are many, many people out there who are having a difficult time. And so it's been a journey of taking that personal experience, and then figuring out how it might apply to other people over time.

What does studying happiness look like for you?

At first, it started with reading as many books as I could get my hands on. My dad was the one who got me into it, he was the one who told me that there was a science of happiness. And he handed me a book by Dr. Martin Seligman, who is the founder of positive psychology, and the person who runs this graduate program at the University of Pennsylvania.

For a few years, I just started by directing my own study, and then eventually, I felt like I had hit a wall, that I wasn't getting access to the true sources of information, which was the studies. That's what inspired me to go to Penn to join that program.

My final project at Penn was writing the first version of this philosophy [New Happy] and starting to lay out those ideas. And once I left, I wanted to continue doing that and developing it.

Based on your research, what are some things that people get wrong about happiness, and what actually leads to true happiness?

The subtitle of the book is "Getting Happiness Right in a World That's Got it Wrong." And so the wrong is "old happy." Old happy is a societal set of beliefs and conditions that teach us about what we need to do in order to be happy.

Old happy is the result of these three forces in society: capitalism, individualism and domination, which teach us that we're not good enough as we are, that in order to be happy we have to achieve certain societally-approved goals or outcomes in our lives, and that we have to do everything by ourselves. You are separate from other people and you can't rely on them and you have to carry all of your burdens by yourself.

And these three beliefs are, I argue, the source of our misery. The shift we want to make to start living a New Happy life is recognizing that we are all worthy exactly as we are, that we all have unique gifts and talents that are within us that can be shared and expressed on our own unique path. And we're connected to other people, and so the best way to use those gifts is in service of them in order to contribute to their well-being.

I thought it was very interesting that you've formed this "New Happy" community. What's it like and how do you all connect with each other?

When I started "The New Happy," it began as a newsletter. Eventually, I realized I had to get on social media and start sharing there. The New Happy began with a handful of followers who were really passionate about investing in their well-being and trying to change the way that we lived. I started to build the community by doing things like providing free challenges every week. So, there would be daily activities for people that they could do to inform their well-being.

We do community check-ins every week where people share what they're struggling with, and then I connect them with resources or tools or people that can help. A lot of the content is driven by the community members. Those questions and feelings that they have, I then use them to develop all of the content that's made, so that we're really addressing people's core needs and meeting them where they're at.

I think, ultimately, my hope is that The New Happy becomes a movement of people who want to redefine happiness, and who feel motivated to come together to do that. So, my intention has always been that this should be something that's driven by a community because I believe that that's the only way we can make change happen.

This interview has been edited and condensed for clarity.

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