An insider told PEOPLE: 'She and Abel have been going back and forth for a few months about their relationship. It's been hard with him being on tour and her shooting in New York.'
Amid the breakup, Gomez has been spotted spending time with Justin Bieber, who she dated on-and-off from 2011 to 2015.
The former couple attended church together and were photographed by TMZ grabbing breakfast at a cafe in California.
It’s been a challenging year for Selena, who revealed in September that the reason she quietly stepped back from her career over the summer was because she was recovering from a kidney transplant.
The breakup comes as a shock to fans, as the couple were not shy of sharing details about their budding romance to their social media pages, and even attended several high-profile events together - including the Met Gala.