Moore could not bring himself to get on a plane and leave his family and informed the Cowboys of his decision Wednesday morning.
"I was wrestling with it all day, going back and forth with my wife and family. Finally, we decided, 'Let's go ahead and do it.' I didn't sleep at all. I was wrestling with it. I realized it was too late in the game to uproot my family. I called my agent and said, 'I can't do it,' " Moore told ESPNNewYork.com's Rich Cimini.
"I played the game for 10 years. I lived in a house. I didn't have to go from team to team, so this would've been a big transition for me. You really don't grasp it until you actually agree to something. Then it was like, 'Wow, I have to leave tomorrow for California,' " he said.
In deciding to retire, Moore passed up a possible $2 million in 2013, a league source told ESPN NFL Insider Adam Schefter. He was to receive a $500,000 signing bonus, a base salary of $1.25 million, which was fully guaranteed, and a $250,000 play time bonus in his one-year contract.
Moore, 33, played for offensive coordinator Bill Callahan for four years with the New York Jets. He spent his first 11 seasons with the Jets, starting 142 of 144 games in his career and every game since 2005.
"I've been truly blessed. I don't have any regrets about my career. I gave it my all. I'd like to be known as a dependable guy who showed up for work every day and gave it his all," Moore said.
The Cowboys were interested in Moore because Nate Livings is expected to miss two to four weeks because of knee surgery last week and Mackenzy Bernadeau returned to practice late last week after missing the first two-plus weeks with a hamstring injury.
"We had conversations with him and we thought he might come in and help our team out," Cowboys coach Jason Garrett said Wednesday. "The conversations were way down the road and we thought we were close to an agreement with him, and he decided when he awoke up this morning he didn't want to play football anymore. So we respect that decision. We'll continue to try and evaluate that position as we go forward."
Moore was involved in the infamous "Butt Fumble" on Thanksgiving Night last season in a play in which Jets quarterback Mark Sanchez slid into Moore and the fumble was returned for a New England Patriots touchdown.
"It's amusing to me to me that people think it's so amusing. The way I look at it, I don't think it should have any link to my career. I don't think it stands for what I was as a player for 10 years. I really don't give it much thought," Moore said.
Garrett was asked about veteran free agent Brian Waters, who last played in 2011 for the Patriots, as a possibility.
"Brian Waters has been a really good player in this league for a long time," Garrett said. "As you guys know, I think he's a six-time Pro Bowler. He's an NFL Man of the Year, played a long time in Kansas City a few years ago, he came late to New England and had a Pro Bowl year for them when they went to the Super Bowl. The biggest issue for Brian right now is he hasn't played in 18 months. You have to factor those things in."
ESPN NFL Insider Adam Schefter, ESPNNewYork.com's Rich Cimini and ESPNDallas.com's Calvin Watkins and Todd Archer contributed to this report.