"My ex-wife was there in the room with me," he says about waking up from a coma. "After all the sh** I had done, I was surprised to see her. Honestly, that's when I knew that I was probably in bad shape."
Odom says that during the time leading up to his medical emergency, he was doing cocaine daily.
"Pretty much every second of free time that I had, I was doing coke," he writes. "I couldn't control it. I didn't want to control it."
"Rick James said it best. 'Cocaine is a hell of a drug,'" he continues. "It's a hell of a drug. It will make you do things you never thought you’d do. It will turn you into a different person. It will put you in situations where you say to yourself, 'How the f**k did I get here?'"
Odom dealt with trauma early in his life, losing his mother, Cathy, to colon cancer when he was 12 years old. The athlete calls his mom the "center of the universe" and says his dad wasn't in his life growing up because of his own problems with addiction.
"The day that she passed away, I remember going to see her, and I remember how the cancer had just ravaged her body," he recalls. "Like if I could go back to that time, and you could put me in that room, I probably wouldn't even recognize who she was. Her face was so small and she was bleeding out of her mouth. And she kept saying [his nickname] 'Mookah, Mookah….'"
"I just sat right next to her bed, and one of the last things she said to me … I still think about it every day," he continues. "She said, 'Be nice to everybody, Mook.' I don't think anything can prepare you for losing your mother at 12 years old. It leaves a mark on you. I don't care how strong you think you are."
Odom was then raised by his grandmother and says he tried cocaine for the first time around the time that she died -- when he was 24 years old and on vacation in Miami.
"When I did coke, I felt good for a minute," he writes. "I stopped having so much anxiety. I didn't think about the pain. I didn't think about death. So I kept doing it more and more, but I was still in control. It wasn't like an everyday thing."
Though his life spun out of control when his son, Jayden, died from Sudden Infant Death Syndrome in 2006 at just six months old.
"Man, my son was vivacious," Odom shares. "Real lively. Whenever I used to walk into a room, he would just like … look at me, and stare. Of course, he couldn't talk, but he just used to stare. He used to use his eyes a lot -- let me know that he kinda understood. Like, 'Yeah, that's my dad. What's up, Dad?'"
"I just seen him," he recalls. "Gone? How the f**k is that even possible? How can he be gone?"
Odom is still grieving from the loss.
"I used to think about what he would look like if he was still here. Actually, I still think about it almost every day," he admits. "No explanation. No answers. Just … gone. Like that. And you're supposed to just accept it. You're supposed to live with that."
Odom says his drug habit escalated from there and that things got "dark as hell" in his early 30s, as his basketball career also started to wind down. Though he doesn't name names, he says his rock bottom was when his wife at the time walked in on him in a motel doing cocaine with another girl.
"I'm a millionaire," he notes. "I'd made it out of Jamaica, Queens, and won two NBA titles. And I'm in a motel, with some random person, doing coke. But I just wanted to get high with this girl, and I had no other place to go. I couldn't take her home. You know, I was being a scumbag. Nothing else I got for that. No excuses. No bulls**t. That's just the truth."
He fully acknowledges being unfaithful and his damaging actions at the time.
"That's the thing people don't understand," he writes. "Anybody who's lived a complicated, drug-infused life like I’ve lived knows the cycle -- with women, cheating on my wife, sh** like that. Nights when I should have been asleep. Nights when I stayed up sniffing coke. Lot of those nights. When your heart is beating fast. When you should know better. When you’re just riding that roller coaster, man."
"My di*k and my habit took me down all the roads that you don't ever wanna go down," he says bluntly. "A lot of great men are fools to that. Fools to that. ... You think I wasn't feeling shame? You think I was blind to what I was doing? Nah, I wasn’t blind to it. Shame … pain. It's part of the whole cycle. My brain was broken."
Odom credits rehab and therapy with getting him to a much better place these days. He's also close with his children, 16-year-old Lamar Jr. and 18-year-old Destiny.
"I'm sober now. But it's an everyday struggle," he acknowledges. "I have an addiction. I'll always have an addiction. It never goes away. I mean, I want to get high right now. But I know that I can't if I want to be here for my children."
"Every morning when I wake up, I look at the same pictures," he continues. "Pictures of people who are gone. My mother. My grandmother. My son Jayden. My best friend Jamie. People who are still here. My two beautiful kids. I just look at their faces for a few minutes, and it's like a reminder of what life is supposed to be about. I feel warm. I feel an energy. I feel love. That sh** gets me through the day."
ET's Lauren Zima spoke with Odom at the Igo.live social media launch party at the Beverly Wilshire hotel on Wednesday night, where he said he was currently "in a great place right now."
"I'm doing great," he said of his sobriety. "One day at a time."
Odom also briefly talked about his relationship these days with ex-wife Khloe Kardashian and her famous family.
"I mean, it's distant, but they're always on my mind and my heart," he noted.
Odom posed with Blac Chyna at the event, and earlier this month, he talked to ET about Chyna's legal drama with his former brother-in-law, Rob Kardashian, when we caught up with him at the Kids' Choice Sports Awards in Los Angeles.