As the investigation continues into last week's apparent murder-suicide of Levens, 28, and his wife, Sara McLean-Levens, 25, details are emerging of his downward spiral.
"Justin was a self-made man who literally fought his way to the top," close friend Tom Atencio tells PEOPLE. "He was a gentle soul who struggled with life. Anyone who grew up under his circumstances would struggle, and unfortunately it got the best of him. He just had some personal demons that he couldn't overcome."
Levens was raised in the projects in Philadelphia, never knew his real father, and was on his own since age 15, Atencio says, adding that "a lot of people let him down in life."
String of LossesAtencio says a string of losses in the mixed martial arts circuit contributed to Levens's stress: With his first professional fight in 2004, Levens rocketed to fame with an undefeated 7-0 record in different leagues – only to hit a losing streak.
His last five matches were all losses.
"Fighting was Justin's life but it wasn't going well for him," Atencio says. "I know he was considering leaving the sport. But Justin was a fighter, I don't know what else he would've done."
Earlier this year, Levens was suspended by the California State Athletic Commission after testing positive for a pain-killing medication.
Signs of TroubleSigns of trouble at the Laguna Niguel, Calif., home of Levens and his wife were apparent in the weeks leading up to their deaths. Deputies responded to their home at least twice in the last month, including a recent visit for a possible drug overdose, says Orange County Sheriff's Department spokesman Jim Amormino.
Pain-killing and anti-depressant type drugs were found in the home following the discovery of their bodies, Amormino said.
And according to the Los Angeles Times, Levens was convicted in 2003 of spousal injury, although details on that incident weren't immediately clear.
"Justin had a rough life; he was a good kid and was trying to get on the right path," Atencio says. "This is a total tragedy and all you can do is wonder. No one saw this coming in the manner in which it happened."
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