Pain is a fighter's constant companion. Few men alive are as intimately acquainted with the pain that is omnipresent in combat sports as much as Justin Wren.

Not long after he was out of high school, the 18-year-old Wren was living at the Olympic training center in Colorado Springs, Colo., when he suffered an injury that dramatically changed the course of his life.

View photos Justin Wren poses with some Pygmy children. (Special to Yahoo Sports) More

First, it led him on a downward spiral toward addiction and depression. He became, he says almost casually, "a depressed, drunk, drug addict."

"Toward the end of my fight career, right around 'Ultimate Fighter' time, right after that, I was basically hiding a drug addiction," said Wren, who was coached by former light heavyweight champion Rashad Evans on Season 10 of the UFC's reality series in 2009. "It was mainly to opiates, narcotics and pain pills, but I was also doing cocaine a lot and medical marijuana."

It's best to know where Wren has been to better understand where he is in his life today as he prepares to make a comeback.

Wren is now a hero to thousands of Pygmies from the Congo, who are known as either "The Forest People" or, as they call themselves, "The Forgotten People."

How he got to this stage, where he’s helped these largely helpless tribes of people buy land, find clean water and learn to grow their own food, tracks back to an agonizingly painful elbow injury he suffered in 2005.

All Wren thought of during his time at Bishop Lynch High School in Dallas was fighting.

After winning two national high school championships, Wren planned to wrestle at Iowa State, where he would have been coached by the legendary Cael Sanderson. But before he ever made it to Ames, he suffered a gruesome injury in December 2005 during a match with two-time Olympian Dremiel Byers at the Olympic training center.

"I got caught in a funky position and I was only down a point and I really didn't want to give up another one," Wren said. "So in a scramble, I really got caught in a bad position. I didn't want to be down two more points, so I kept fighting until my arm snapped.

"If you put your arm kind of behind your back to the point where your forearm is on your lower back, but just the other way. It was like putting your hand on your back with your hand facing the sky and kept cranking it back the other way until it snapped."

He dislocated his elbow, tore the ulnar collateral ligament and broke several bones. Doctors told him there was a 35 percent chance he wouldn't be able to compete again.

That sent him into a depression. He was facing a surgery in which a tendon from his hamstring would be taken and inserted into his elbow and a nerve in his elbow would be moved.

View photos Justin Wren stands with a Pygmy tribal chief. (Special to Yahoo Sports) More

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