"I was chubby as a kid, but it didn't become a huge problem until late middle school, early high school," the Southern California native said.
As a teen, a series of health problems caused Bartley to go from overweight to obese. "When I was 12 years old, I had what's called an ovarian torsion. That's basically when the ovary twists on itself. My doctor decided to remove it entirely," she said.
Two years later, Bartley had surgery to untwist her remaining ovary, which led to menopausal symptoms.
"I was trying to live life as a normal teenager, and I was having hot flashes on the way to class," she said.
At the time, doctors told her she might never have kids.
"I've always wanted to have kids. ... I fell even deeper into a depression and really started struggling with a binge-eating disorder."
Between the ages of 16 and 17, Bartley gained more than 60 pounds.
"I was binge-eating multiple times a day. I would get enough food for three to five normal-size meals, and I would park my car in a deserted parking lot and stuff myself until I was sick," she recalled.
Bartley was close to 300 pounds at her highest weight.
"I have always been a future-oriented person," she said. "I remember one day having this overwhelming sense that none of this matters if I don't take care of my weight first."
'Take my body back'
Bartley's first step was starting a workout program. "It was time to take my body back. Take my life back," she said.
Jami Klein worked as her personal trainer. "She was shy and a little uncomfortable when she first came in. She didn't really enjoy fitness and had no idea where to start," Klein said.
The trainer got Bartley working out for 30 minutes a day, three times a week, to start.
She soon lost enough weight to qualify for a vertical sleeve gastrectomy, which reduced the size of her stomach.
"I was able to use the surgery as a tool to lose weight. But as time went on, I realized it was becoming a lot more about what I was doing, the habits I was forming and the actions I was taking," Bartley said.
She turned to social media for motivation.
"Probably the No. 1 thing that has kept me accountable has been sharing my weight-loss journey on Instagram," she said.
At first, Bartley used Instagram to follow other people. But the more she shared, the more encouragement she received.
"I was even sharing non-scale victories. The first time I was able to shop at a normal store, I remember sitting in the dressing room crying because I fit into an extra-large top," she said.
Now, Bartley is inspiring others, with more than 170,000 followers on her Instagram account, @morganlosing.
"Once people started following me, I really wanted to be a good example of changing for your health and not because you hate yourself."
Bartley lost 115 pounds, and she's learned to enjoy the journey.
"More than anything, I just want to be healthy and strong," she said. "As the journey goes on, the number on the scale becomes a lot less important."
For someone who used to hate going to the gym, exercise has become an outlet for Bartley.
"She changed tremendously," said Klein, her personal trainer. "She started to have more fun and feel more comfortable. I started to see her self-confidence emerge."
Now, Bartley is working toward her personal trainer certification to one day help others.
"Down the line, I could see myself working with people who have massive amounts of weight to lose," she said.
She also froze her eggs and hopes to start a family one day.
"I feel confident knowing that my body's not going to be the thing that stands in the way of me and what I want in life."
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