The British racer earned a victory in Budapest on Sunday (28 July), and later suggested he'd been thinking about the former Pussycat Doll throughout the race.
He said after his win: "The thought on my mind through the whole race was of someone who is special to me and I wanted to dedicate it to her."
Lewis and Nicole ended their five-year relationship earlier this month, with reports claiming it was because of their hectic schedules. He's been travelling all around the world during the Grand Prix season while she's begun work on the new series of X Factor.
Mercedes driver Lewis later admitted the split had turned his world "upside down", saying: "I'm trying my hardest to be positive but I'm going through a really tough time at the moment with the loss of someone really, really special in my life."
The high-profile couple met at the MTV Europe Awards in Munich in 2007 but briefly split in 2010. They then reconciled the following year.
Following yesterday's win in a scorching hot Budapest, Lewis again said it hadn't been the easiest few months, and suggested it was "odd" racing without Nicole in the paddock.
"It feels a little bit odd without that someone here – but I would say now that this is one of those races you want to dedicate to that someone," he said. "For the next few days, this will keep me riding high. It is a bit of a Band Aid that will cover me for some time."
Lewis appeared to be thinking about Nicole last week too when he posted a cryptic message on Twitter.
He tweeted: "If you've found that special someone, don't EVER let them go no matter what!! Nothing in this world is more important..."
Lewis also referenced his ex in a Twitter posting on 24 July, writing: "Nicole once told me how beautiful Vienna was, now I see she was right. Have training here tomorrow, 100km bike ride. Should be good!"
If you've found that special someone, don't EVER let them go no matter what!! Nothing in this world is more important...— Lewis Hamilton (@LewisHamilton) July 19, 2013
Nicole, meanwhile, has been working on the tenth series of X Factor, which just wrapped up the audition stages this month.
The 'Boomerang' singer will join Gary Barlow, Louis Walsh and the returning Sharon Osbourne on the judging table and will be hoping to get her second win in a row.
In her debut year last year, she won the show with her singer-songwriter contestant James Arthur, with her other artist, Jahmene Douglas, coming second.
Lucy Mecklenburgh, Michelle Keegan, Denise Van Outen: the weekend's top stories in pictures
Copyright: Twitter Lucy Mecklenburgh