Taylor Swift has fallen in love... again. She does seem to fall in and out of relationships with relative ease, but her current romance with the Scotland-born DJ Calvin Harris seems like her most serious yet.

Over six months, the couple has grown so close that Swift refers to her new boyfriend by his real first name, Adam, according to Us Weekly.

"Taylor always calls Calvin by his birth name, Adam, and never Calvin in private," a source told Us Weekly. "Taylor gets all dressed and glammed up whenever she is going to see him to look her best."

The couple was first linked back in March when Swift flew to Las Vegas to watch him perform. They took their relationship public at the Billboard Music Awards in May, sitting front row and embracing every time the "Shake It Up" singer won an award.

"She's head over heels," the source said. "She hasn't been in love like this before!"

Swift's ex-boyfriends are plenty (and most have inspired a song or two). Harris' ex-girlfriends include models Anne V and Aarika Wolf as well as singer Rita Ora.