You're looking at the "Holiday House" that Taylor Swift refers to in "The Last Great American Dynasty." Swift bought the coastal mansion for $17 million in 2013, long after its former inhabitant, Rebekah Harkness, had passed away (via The New York Times). 

Most of the references that Swift makes in "The Last Great American Dynasty" are directly out of Harkness's autobiography. Like the woman in Swift's song, Harkness was from St. Louis. She was a divorcee when she married oil baron William Hale Harkness (aka Bill), who died of a heart attack. Incidentally, as Harkness herself told it, she married her first husband, Dickson Pierce, because she ”had nothing else to do."

As for the other references in Swift's song, including the "loud parties," the blowing "money on boys and ballet" and the "losing on card game bets with Dali"? Harkness, the founder of the Harkness Ballet, threw parties where swimming pools were filled with champagne complete with celebrity guests such as Howard Hughes and world-renowned yoga guru, B.K.S. Lyengar (via The Day). As for Salvador Dali? He, too, is rumored to have visited Rebekah Harkness.