"Louis and Eleanor split up two weeks ago," a rep confirms to PEOPLE. "They have not announced this as they wanted some privacy during this time."
"Louis is really upset about it all," a friend of the 23-year-old singer tells PEOPLE. "They tried really hard to make it work but it was just impossible – he's away for nine months a year and they just grew apart."
Calder lives in Manchester, England, where she attended the University of Manchester. Tomlinson, meanwhile, has been crisscrossing all over the globe with his band. The couple had been dating since fall of 2011.
It's been a difficult time for the British band as Zayn Malik recently announced that he was taking a break from the group's On the Road Again world tour due to stress.