The 22-year-old, who dated Jake Gyllenhaal two years ago, has written a philosophical track 'All Too Well', which refers to her break-up from the actor, the Us magazine reported.
Swift has called 'Red' her most "adventurous album yet". The singer found it difficult to pen 'All Too Well'.
"'All Too Well' was the hardest to write because it took me a long time to filter through everything I wanted to say. It started out being a 10-minute song, which you can't put on an album. I had to filter it down to a story that could work in the form of a song," she said.
In the track, Swift reflects on her 2010 Thanksgiving outing with Gyllenhaal, 31, opening about spending the holiday at his sister Maggie Gyllenhaal's home in Brooklyn, NY.
Swift even sings about a mysterious black and white striped scarf both she and Gyllenhaall wore during their courtship.
"Left my scarf there at your sister's house / And you still got it in your drawer," Swift's lyrics read.
Swift was dumped by Gyllenhaal around Christmas in 2010 by a phone call. The actor was apparently uncomfortable about their age difference and the media hype surrounding the romance.
After splitting from Conor Kennedy in October, Swift is now "officially hanging out" with One Direction's Harry Styles, whom she recently bonded with at an X Factor taping.
Her other famous exes include Joe Jonas, Taylor Lautner, John Mayer and Cory Monteith.
