Shannon Petitjean

Shannon Petitjean, before and after losing nearly 200 pounds and becoming a marathoner. (Barbara Haddock Taylor / The Baltimore Sun and Courtesy Shannon Petitjean / October 11, 2013)

Five years ago, Shannon Petitjean weighed more than the biggest Raven, smoked three packs of cigarettes a week and drank too much.

No more.

Petitjean, of Leonardtown, will compete in her first Baltimore Marathon on Saturday having shed 190 pounds and quit smoking and drinking.

"Half of me, literally, is gone," she said. "I have another chance at life."

The race is the second of three marathons Petitjean plans to run this month. The 36-year-old, who'd never run one before last Sunday, completed her first race in Corning, N.Y., in 5 hours, 21 minutes. In two weeks, she'll run the Marine Corps Marathon in Washington.

"I do everything in excess," she said. "Only now, I'm on to healthier things."

It shows. The 5 foot 9 woman who once weighed 355 pounds is now a lean 165. Her clothes size has shrunk from a 26 to a 6. To her children, who once called her "Big Mom," she's just Mom. Friends who've seen her jogging mile upon mile through St. Mary's County have dubbed her "The Shannonator."

"She's a totally different person, from the inside out," said Mandi Kuidlan, a lifelong friend. "Shannon was always very unhappy with herself. She's gone through some dark times and always struggled with her weight. I've never seen her at [165 pounds], not even in middle school.

"I don't know what finally kicked it into gear for her, what gave her the strength to do this, but her story is amazing. If Shannon can do it, anybody can."

Hers was not an overnight success, Petitjean said. She hit bottom in 2008, after the birth of her second son.

"I remember going to the health clinic, getting on the scale and facing the other way because I was too embarrassed to see my weight," she said. It was 355 pounds.

That was her tipping point.

"It stung," she said. "I'd always been the funny one, the loud one. I figured if I was that way, people wouldn't look at my girth. At eight, I was ordering off the big menu at Burger King. When I hit middle school [in Lusby, Calvert County] I weighed over 200. All my life, I'd go to Chinese buffets and head back to the table a third and fourth time.

"I'd try fad diets for a day or two and give up. Eventually I didn't want to get out of bed, but I had two kids and a house to take care of. I didn't want to go out because I was ashamed of the way I looked and felt. My drinking was out of hand. And when I got upset with the children, I'd go out on the porch with a cigarette to calm down. That was supposed to solve my problems."

At 31, she was determined to change.

"Maybe it was having to always shop for larger clothes, or not being able to get on rides at the local fair, or being too flat-out tired to keep up with the kids," she said.

Petitjean toyed with other diets, started eating better and joined Food Addicts Anonymous, a 12-step program in which she measured her food, swore off flour and reported daily to a sponsor. By March, 2009 she'd lost 150 pounds but then dropped the program, tired of its "boot camp" routine.

Her weight crept back to 250. There she hovered for nearly two years until, in February 2011, a friend suggested she join Weight Watchers.

"That's the only thing I hadn't done," she said.

Again, the pounds began to melt. That April, her mother talked Petitjean into walking a local 5K (3.1 miles) for charity.