'Beverly Hills, 90210' alum Brian Austin Green lacked 'confidence' to fix 18-year rift with Tori Spelling

In an exclusive interview with Fox News Digital, Green - who was set to co-host the ultimate '90s After Dark Party with Spelling at Voltaire at The Venetian Resort Las Vegas Dec. 28 before Spelling postponed the event due to illness - reflected on their decades-long friendship, the 18-year silence that followed and the personal growth that ultimately brought them back together, stronger than ever.

"Tori and I have a really special, unbelievable bond," said Green, who portrayed Spelling's onscreen love interest, David Silver, in the beloved '90s series for 10 seasons. 

"We are a month apart in age. We were the youngest on the show. We did everything together because that was sort of David and Donna (Martin). That's how everybody booked it. All the trips, all the press stuff, all the things. It was always the two of us.

"So, not talking for, which is crazy, 18 years, that's crazy to think. Again, neither one of us completely knows how it happened," he continued. "We've talked about it, and we've gotten into it a little bit, but life is just complicated. And things just sort of happen sometimes when you're in them. 

"And we were so young that we weren't strong enough in ourselves to reach out to the other person and go, 'What the f--- is going on?' I didn't have enough self-confidence to do that and be willing to hear something I had possibly done wrong. It was easier. Ignorance is bliss in a situation like that."

WATCH: 'BEVERLY HILLS, 90210' ALUM BRIAN AUSTIN GREEN LACKED 'CONFIDENCE' TO FIX 18-YEAR-LONG RIFT WITH TORI SPELLING

"What I remember is going by [Spelling's then-boyfriend and their former costar] Vincent [Young]'s house to see you multiple days after we wrapped and trying to keep a connection going. But it got to the point where I just never got that from you," Green explained.

"And then I remember being at the '90210' DVD release party, and you were married to [now-estranged husband] Dean [McDermott] and I was with [now-ex-wife] Megan [Fox] when we were still just dating. You guys got there, and you never said hello to me once. I just kept missing you guys, and then you were gone."

The duo eventually reconnected and became closer than ever. 

"When we reconnected, it was really this moment of what is more valuable in this situation, in rehashing the past and vigorously trying to figure out what was going on and still kind of being distant or moving past it and recreating what this relationship and friendship was for years," he said. "And I'm so glad that we took that route. I really am.

"She's an amazing human being," Green continued. "She is honest. She will have your back to the very end. She'll fight for you. She's a ride-or-die. And there aren't many people like that in my sphere. So, I'm so glad that she's back in it, and I hope she feels the same way."

"She's great because she is a constant reminder to really enjoy life and laugh and have fun," Green continued. "She's a really lighthearted person. So she's great. When life gets really serious, and it's really exhausting, to have somebody that is just as silly and can be as ridiculous as she can. And she is as self-deprecating as she is, like, 'We'll f--- with people.' 

"So, it's really fun because she'll say something about me, and then I'll say something about her, and then she'll go, 'Yeah, you're right.' And, so, it's like we're always crossing the line of taking things that could be misconstrued as, 'Oh, that's really going to rub somebody the wrong way,' and it never does with us."

At 52 years old, Green, who is engaged to former "Dancing with the Stars" pro Sharna Burgess, said he's content with how things have panned out in life. 

"I wouldn't give my younger self any advice because everything that I've gone through has led me to the point that I'm at now, which I love," said Green. "And I always say it's not the successes that I've learned from, it's the failures because those are the things that make you go back to the drawing board and reassess what it is you're doing and what worked and what didn't. 

"I think, honestly, if you step back, it's a lot easier than you've ever thought it was. I always made things so difficult because I was always concerned about how something made me feel or how secure I felt. And I really made situations so much harder than they had to be."

The father of four said he was looking forward to stepping back into the '90s with Spelling Dec. 28, prior to the postponement.

"And we sort of host this night with all '90s music. It's to create something that is fun for the generation that we are from," he said. "It's exciting to get back into a time before the internet existed and when it was just all about the culture and the music and just dancing and having fun and not being so caught up in everything else that's going on."