"It's something we'll always be deeply and unreservedly sorry for," Reynolds, 43, explained. "It's impossible to reconcile."
"What we saw at the time was a wedding venue on Pinterest," he added. "What we saw after was a place built upon devastating tragedy."
Reynolds -- who shares three daughters with Lively: James, 5, Inez, 3, and a third whose name has not been publicly revealed, born in October -- said that he and his wife "got married again" years later.
"But shame works in weird ways," Reynolds explained. "A giant f--king mistake like that can either cause you to shut down or it can reframe things and move you into action."
"It doesn't mean you won't f--k up again," he continued. "But repatterning and challenging lifelong social conditioning is a job that doesn't end."
Through his production and marketing agency, Maximum Effort, the actor is making an effort to create change within the industry by stressing diverse hiring and providing employees with equity.
"Representation and diversity need to be completely immersive," he told Fast Company. "Like, it needs to be embedded at the root of storytelling, and that's in both marketing and Hollywood. When you add perspective and insight that isn't your own, you grow. And you grow your company, too."
Although Reynolds and Lively, 32, hadn't yet addressed the criticism over their wedding venue, in their social media posts about their donation, the pair vowed to do better in the future and keep themselves and their three daughters more informed of the world around them.
Admitting to their "own blindness" in the past when it came to white privilege, Reynolds and Lively said they're "ashamed" over how "uninformed" they've been in the past.
"We never had to worry about preparing our kids for different rules of law or what might happen if we're pulled over in the car," they wrote. "We don't know what it's like to experience that life day in and day out. We can't imagine feeling that kind of fear and anger. We're ashamed that in the past we've allowed ourselves to be uninformed about how deeply rooted systemic racism is."
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"We've been teaching our children differently than the way our parents taught us," they continued. "We want to educate ourselves about other people's experiences and talk to our kids about everything, all of it... especially our own complicity. We talk about our bias, blindness and our own mistakes. We look back and see so many mistakes which have led us to deeply examine who we are and who we want to become. They've led us to huge avenues of education."
"We're committed to raising our kids so they never grow up feeding this insane pattern and so they'll do their best to never inflict pain on another being consciously or unconsciously," they wrote. "It's the least we can do to honor not just George Floyd, Ahmaud Arbery, Breonna Taylor and Eric Garner, but all the black men and women who have been killed when a camera wasn't rolling."
In addition to their donation to the NAACP, the two promised to "stay educated" when it comes to local elections as well, saying they'll take it upon themselves to know everyone's "positions on justice."
"Mainly, we want to use our privilege and platform to be an ally," they concluded. "And to play a part in easing pain for so many who feel as though this grand experiment is failing them."