The British snooker star became the oldest winner of the event in York on Sunday, 30 years after he claimed his first title at the tournament at the age of 17.
O'Sullivan, who turns 48 on Tuesday, wrapped up a 10-7 win with an exhibition-style finish of 129 in raucous scenes at York's Barbican.
Hauled back from 4-1 and 7-5 leads by Ding, the world number one dug deep when it mattered and consecutive breaks of 100 and 74 set him up for his final flourish.
But O'Sullivan was low key after his victory, admitting it lacked the "buzz" of some of his earlier successes, and said he had even found himself struggling for motivation as the opening session loomed.
"I'm not sitting here with a massive grin and super-excited," he said. "I just go through the motions a lot of the time.
"It's great to win and I give my best when I'm out there and I want to win, but it's not the same excitement as years ago when I was winning my first world and UK and Masters titles, and you're buzzing.
"Don't get me wrong, it's still a nice feeling and a job well done, but I get more of a buzz from going for a run in the morning or having breakfast with my mate.
"I don't actually feel like ever playing. Once you get down there you think you're glad you've done it, but even in this match today I was thinking I didn't feel like it, I'd rather sit on my bed and watch a bit of Netflix. I feel like that a lot of the time."
Ding, who was also beaten in last year's final, by Mark Allen, said: "The first half was disappointing because I had a chance to win more frames but 4-4 wasn't too bad because I was 4-1 down. I came back to 7-7 but he played so well.
"All I could do was play good safety and make breaks. He just pushed me to make mistakes and it's all I can do -- I can't do anything else out there."
