David, 34, revealed the news in an interview, which has come weeks after he was spotted holding hands with 27-year-old Mollie in central London.
Speaking to Evening Standard Magazine, David even said that Mollie has her own drawer of clothes at his bachelor pad.
The drawer apparently has the word 'Mollie' written on it in chalk and is located in the Dolce & Gabbana model's giant walk-in wardrobe.
Things must be serious!
When asked about the drawer, David told the publication: "That may be there for a while, so, uh…" He then added: "Even though she steals all my clothes..."
David and Mollie dated for 10 months in 2011 but, despite things appearing to be blissful between them, they suddenly split.
In July of this year, however, Mollie and David were apparently spotted having dinner together. Months earlier, Mollie had broken up with her US music producer boyfriend Jordan Omley.
We hope the couple can make it work this time!
Are you glad to see Mollie and David back together? Tell us below, as the best comment from across the website each week wins £50.