He also revealed to Yee that he fell in love with Pinkett Smith during their affair.
"I totally gave myself to that relationship for years of my life, and I truly and really, really deeply love and have a ton of love for her. I devoted myself to it, I gave my full self to it – so much so to the point that I can die right now and be OK with knowing that I truly gave myself to somebody," he said.
"And I really loved a person, I experienced that and I know what that feels like – and some people never get that in this lifetime. I know that I am completely blessed and this conversation is difficult because it is so much, that it would be hard for people to understand but, once it starts to affect me and my livelihood, I have to speak up about my truth."
While Pinkett Smith's representatives have reportedly denied the claims, she has previously admitted having a sex addiction.
During a recent episode of her Facebook Watch series Round Table Talk, she touched on the subject again:
"When I was younger, I definitely think I had a sex addiction of some kind, yes, that everything could be fixed by sex. You know what I'm saying?'"
She has also previously shut down rumours that the couple is into the swinging scene.
When questioned about it on a US TV show, Jada said: "The craziest rumour? That Will and I are swingers. It's constant.
"And I'm like, 'Yo I wish! I wish!'"
However, they have both admitted to having an "open relationship".
In 2005, Will told the New York Post, "In our marriage vows, we didn't say 'forsaking all others.'"
"If it came down to it, then one (spouse) can say to the other, 'Look, I need to have sex with somebody. I'm not going to if you don't approve of it — but please approve of it'," he added.
Back in 2011, US InTouch magazine claimed that Will found Jada with Jennifer Lopez's then-husband Marc Anthony at their Hidden Hills mansion in Los Angeles.
Jada reportedly briefly moved out of the family home the next day.
This wasn't the only time rumours of celebrity affairs plagued the couple. In 2013, Will Smith was rumoured to have had an affair with co-star Margo Robbie.
Will and Jada met for the first time in 1994, on the set of Fresh Prince of Bel Air when she auditioned to play his on-screen girlfriend. She did not end up getting the role, but developed a romance with the actor who, at the time, was still married to Sheree Fletcher.
Will and Sheree divorced the same year their relationship became official.
Their daughter Willow, now 18, has said her first introduction to sex happened when, as a teenager, she walked in on her parents having sex.
"I was going downstairs to get some juice and I saw for a little moment and I ran away. I was like, 'Oh my God, this is so crazy. What did I just see?'"
Jada Smith believes that, while it's not all about sex, "great sex" is an essential part of a good relationship, especially one that goes back as long as her marriage does.
"Especially after being in a union for as long as I have been. It gets deep."
