Spain's Rafael Nadal defeated the 26-year-old Serbian 6-2, 3-6, 6-4, 6-1 ysetreday to collect his 13th Grand Slam crown and second title on the New York hardcourts, having also beaten Djokovic in the 2010 final to complete a career Slam.
Djokovic bounced back from that US Open near-miss to have a 2011 season that was among the greatest in tennis history, winning the US and Australian Opens and Wimbledon.
He began the year with a 41-match win streak that was snapped by Roger Federer in the French Open semi-finals on the way to a 10-title season.
So Djokovic knows that the heartache of losing to the world number two again in a US Open final could be what motivates him to an incredible 2014 campaign.
"I have to (use it as motivation). It's part of my life," Djokovic said. "Many times you fall as an athlete and you have to learn the lesson and keep on going, keep on fighting, keep on improving. That's what we are here for.
"I'm still 26 and I believe the best time for my career is about to come. I feel that. As long as I believe it, the fire of the love toward the game is inside of me.
"And as long as that's present, as long as I feel it, I'm going to play this sport with all my heart, as I did in the last 10 years."
Djokovic said he could appreciate the moments of great tennis he played against Nadal in a match that roused cheers from a sellout crowd at Arthur Ashe Stadium, but they didn't outweigh the misery of defeat.
"I'm aware of that. But obviously I just feel disappointed for losing," he said. "It's all sport. You know, tomorrow is a new day."
Djokovic and Nadal contested one point for 54 shots, earning a standing ovation for a moment that the Serb said sums up their rivalry, the most contested one of the Open Era and one that Nadal leads by 22-15.
"I played especially against Rafa on different surfaces points like this where you just feel that there is the last drop of energy that you need to use in order to win the point," Djokovic said.
"It's what we do when we play, always pushing each other to the limit. That's the beauty of our matches and our rivalry in the end."
Djokovic fell to 6-6 in Grand Slam finals with four of them at the US Open, including in 2007 to Roger Federer and last year to Andy Murray. He also lost the 2012 French Open final to Nadal and this year's Wimbledon final to Murray.
But he did win his fourth Australian Open crown in January.
"I wish I won at least one title more, considering the fact I played two finals," Djokovic said. "All the matches I lost, even the French Open, I had that match. I lost it again in semis.
"Overall, it was again a very successful Grand Slam year for me. That's something that I always try to have in the back of my mind."
Djokovic was undone by 53 unforced errors, the most critical in the third set when he let momentum slip out of his hands.
"It's all my fault," he said. "I made some unforced errors in the crucial moments with forehands and dropped the serve twice when I should not have. All of a sudden it's two sets to one for him. Then he started playing much better after that and I obviously could not recover.
"In the important moments he played better tennis and that's why he deserved to win. I was supposed to use the opportunities that were presented to me and I didn't do it. I didn't deserve to win in the end."
But Djokovic doubts he has seen the last of Nadal, whom he rates among the game's greatest of all time.
"Well, 13 Grand Slams for a guy who is 27 years old is incredible," Djokovic said.
"What he achieved so far in his career is something that everybody should respect, no question about it. He's definitely one of the best tennis players ever."