Todd Marinovich: I Don't Want to Die from Drugs ... I Love My Kids

Ex-NFL quarterback Todd Marinovich says his naked drug arrest was a rude awakening about how out of control his substance abuse issues had gotten ... and now he's fighting to live for his kids.

The 47-year-old opened up to TMZ Sports about his life since his arrest back in August -- when cops found him naked in a stranger's backyard -- and how it was the rock bottom he needed to change his life.

"I've been running [from my addiction] for years and it definitely came a time, especially after the arrest, the humiliation that that brought, the self-loathing that I was feeling, where I was finally willing to do the things necessary to get better."

Todd says he's stopped counting the days he's been sober -- instead, he takes a day-by-day approach -- but says he's been getting treatment and he's in a MUCH better place.

"I have never been better," Todd says ... "I think it's a long time and a long journey getting to this point."

Todd's substance abuse issues are well-documented. He's struggled with addiction since he was a star QB at USC in the late '80s, early '90s and has been to rehab several times before.

So, what's different this time around? Todd says he's got two little kids who are motivating him to stay clean.