BOSTON (CBS) -- This marathon runner's story is designed to help others: it's about one woman's iron will to overcome addiction.

"I'm excited, I'm nervous, but I'm very stubborn so even if I have to crawl, I will finish this race," says Kelley Balbi of Ashland.

She's traveled a hard road to get to her first Boston Marathon.

"I am an alcoholic. I grew up surrounded by addiction." Balbi says her parents and her brother have all struggled.

"My college partying didn't stop. I realized within the four years, from the first time I took a sip of alcohol to the last time, that I had the gene, too. I was an addict," she explains.

But when she ended up drunk and hospitalized, that changed. "I got sober a little over eight years ago," she says.

Balbi credits joining a gym for some of her success. "When I was two days sober, I joined a gym. And I didn't know it all the time, but it was really what kept me sober."

That's why she's running the Boston Marathon to raise money for The Phoenix, a sober gym in Boston, a place where people struggling with addiction can not only get healthy, they can also find a community.

"I made it to the other end and I have a house, I have a husband, I have a beautiful daughter. I have a lot to be grateful for," Balbi says.

It was that knowledge that kept her going, training through the winter and the rainy spring, focused on crossing the finish line.

"I think I'm going to be proud. I think I'm going to be excited. I think I'm going to be overwhelmed. I have a feeling there might be a few tears in there."

Balbi says she'll be ready on Monday, rain or shine.

Support Kelley Balbi's cause here.