WILL Smith broke down in tears as he recalled his divorce from first wife Sheree Zampino, branding their split the "ultimate failure".
The actor, 51, also talked about his father, Willard's tough parenting style and the trauma of watching him beat his mother growing up.
revisited the difficult memories during an emotional chat on her Facebook series .
Will married Sheree in 1992 and they welcomed their son, Trey, when was just 24.
Discussing their 1995 divorce - which turned messy due to a custody battle - Will admitted: "Divorce was the worst thing in my adult life, divorce was the ultimate failure for me.
"I've been hurt a lot in my adult life, but I don't think anything touches the failure of getting divorced from my two-year-old son's mother."
Will stepped away from parenting Trey on his father's advice to avoid the youngster witnessing the tension between him and Sheree.
He explained: "That was a difficult time but as daddio said, as soon as Trey was ready, he came looking for his father."
The Bad Boys star teared up as he discussed feeling out of his depth when he became a father to Trey.
"I think that was my first moment of the real weight of parenting [when they brought Trey home]," Will said.
"We put him in the bassinet and Sheree went to sleep and it was like stark terror. It was like, I'm totally responsible for this life and I just couldn't stop going and checking."
His eyes filled with tears as he went on: "I gotta make sure he's breathing and all that new parenting stuff. I just cried so hard, it makes me teary right now.
"[He thought] I can't do it. Like, I'm not the guy. I'm not the guy. I just knew I didn't know nothing."
The Men In Black star then joked to Jada: "Oh man, I'm gonna need to get myself together. I'm gonna have to walk this one off! I need a tissue.
"I thought the Red Couch wouldn't get me like this, I thought the Red Couch was safe!"
After his divorce from Sheree, Will married Jada in 1997 and the pair have two children - rapper Jaden, 21, and singer Willow, 19.
Will also talked about his father's "temper" and how he would "slap or punch or beat" him.
"I loved how my family was, but there were massive, critical deficiencies in my father's parenting that I wanted to correct," he said.
"I remember looking at my father thinking I could do it better than him. My father had a bit of a temper and I was a gentle kid.
"I was not a kid you had to slap or punch or beat, so growing up in a household where physical aggression was approved of, that really chaffed my hide, that hurt my spirit."
He went on: "There's such beautiful qualities that he instilled that are a big part of me ... but as the yin to every yang, I watched him beat up my mother."
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"So the biggest emotional scar I have in this lifetime, he delivered that also. He showed me a lot of things that I wanted to do, but he also showed me the things I would absolutely, positively never do to my children.
"When he would get angry, he would turn into the dumbest person I ever met."
Despite his childhood ordeals, Will said he doesn't hold a grudge against his dad and, in fact, learned parenting lessons from him.
The star explained that his father believed children weren't only taught in school, saying: "His thing was, you can't father from a distance."