Story highlights Brittni Garcia didn't think her weight was a problem until she couldn't fit into her "fat shorts"

At 235 pounds, Garcia always felt like she stood out from her sorority sisters in college

Garcia shed 107 pounds, and now promotes weight training and a healthy diet

Do you have a weight loss success story? Share it with CNN iReport

Brittni Garcia's family didn't go out for walks; they went out for dinner. And when they were at home, they enjoyed watching movies, playing board games and eating big Mexican-style home-cooked meals.

This lazy lifestyle led Garcia to weigh more than 200 pounds by the eighth grade.

"My mom always said, 'You are a big girl. You are just big-boned,'" said the 25-year-old information specialist. "So I just accepted it."

Through high school and college, her weight continued to rise. But even at 235 pounds, Garcia didn't think her weight was a problem -- until she couldn't fit into her "fat shorts" anymore.

That was December 2009.

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It was a typical night for Garcia. She was studying for finals in her sorority house at Eastern Illinois University and wanted to change into some comfortable clothing. She found her red pajama XXL shorts that she normally wore to bed.

As she struggled to pull them up, she realized they were too tight and uncomfortable -- her "big, comfy shorts" no longer fit.

"Tons of emotions ran through my head," she said. "I was afraid that was the way my life was going to be."

That's when Garcia's mentality changed. Being overweight was no longer normal for her.

Heart disease runs in her family, and she realized it was time to address her weight now before it turned into a bigger health problem.

"I wanted to lose weight to challenge myself and show myself I can change, and not change for the world," Garcia wrote in her iReport . "This time, it was for me."

Getting in shape wasn't going to be easy. Going to the gym had been one of her biggest fears for a long time. She was self-conscious about how she looked and sounded when she ran.

"It was hard for me to breathe," Garcia said. "It was embarrassing."

Embarrassment about her weight extended to other areas of her life. Although she was president of her sorority, Garcia always felt like she stood out.

"All the sorority girls had cookie-cutter form, and I looked different," she said. "It was really hard for me to connect."

Garcia's involvement in Greek life perpetuated her unhealthy habits; she often went to bars and restaurants to mingle with her college friends. It was difficult to break the cycle, but she found supportive friends who also hit the gym.

"What I tell people is that you find new friends at the gym," she said. "If you don't have the support, it's really hard to do it on your own."

Garcia found one of her biggest supporters through her sorority. She met Nicholas Monreal at a Greek function, and they began dating when she was at her heaviest. But the days of social functions, bar visits and restaurant outings are long gone for the couple.

"He was there when I realized I wanted to change," she said. "To this day, our dates are to the gym. We see excitement in going on walks and runs."

The couple has been together for four years; he proposed in December. Monreal has noticed a significant difference in Garcia over the past few years -- not just physically.

"She's more energetic ... and she's more willing to try new things," he said "She's just working very hard, and she's a better person for it."

On the right track

Since the beginning of 2010, Garcia has lost 107 pounds.

There were setbacks, the biggest of which came this past August when she was in a car accident. She completed three months of physical therapy and wasn't able to go to the gym and do her daily routines for a month and a half.

She was angry at first -- mad at the person who hit her car and stalled her progress at the gym.

But she got over her initial anger, and Garcia went on a walk. This time, she wasn't alone. Her fiance, her parents, her sisters and her aunt encouraged her to stay active. As a result, Garcia went on walks with them and did yoga at a gym.

After getting back on track with her daily workouts, Garcia realized she also had to better manage her eating habits.

"For the longest, I would go to the gym and go home to eat whatever I wanted," she said. "That's not how it works. I had to learn to eat differently and to learn to like new foods."

She started doing research on proper nutrition. She read books and online articles, shopped at health foods stores and learned to prepare meals that helped her maintain a healthy diet.

Now for two hours every Sunday, Garcia grills chicken, cooks vegetables and packs fresh fruit in preparation for the upcoming week.

"(I) make eating as simple as possible," she said. "If there are a lot of ingredients, I don't want it."

The next step

Down to 128 pounds, Garcia has been left with a lot of loose skin -- particularly around her stomach. She is doing CrossFit exercises and weight training to tighten up the area.

She's also checking off some other goals.

One of the most rewarding moments in Garcia's weight loss journey was completing her first 5K run in 27 minutes.

When she first started training, running three miles took her 48 minutes. Today, she can complete it in less than 25.

"I hadn't been able to walk a lap, let alone run it," she said. "And now when I finish a workout, I really get emotional and I can't believe that I could do it."

She isn't stopping there. Garcia wants to complete a half marathon as well as the Warrior Dash in June. As a result, she might take a pool break in between.

"I really want to fit in my bikini comfortably this summer," she said.

Today, Garcia doesn't shop at plus size clothing stores anymore. She was able to drop from a size 22 to a size 6.

And what happened to her XXL "fat shorts?" She ditched them for a pair of small exercise shorts.

To those just starting their weight-loss journey, she offers this advice:

"Once you start, don't give up. The hardest thing to do is to continue. If you have a bad day, don't make it a bad week."