This real-life Titanic passenger’s heart did go on — in a century-old love letter.

James Cameron’s 1997 blockbuster “Titanic” famously revolved around the romance between Leonardo DiCaprio’s Jack Dawson and Kate Winslet’s Rose DeWitt Bukater — two fictional characters created by Cameron himself.

But now, a never-before-seen letter has revealed that there actually was a passenger aboard the boat pining over a woman named Rose.

Ernest Tomlin, a 21-year-old third-class passenger, boarded the Titanic in Southampton, England, on April 10, 1912, and wrote a five-page letter to his family just hours later.

The missive was sent out from Queenstown, Ireland — the ship’s last port of call — the following day.

In it, he reveals his heartbreak over a mystery woman named Rose.

“Dearest Mother and

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