"They initially split about six weeks ago, but that can take a little time to extricate. But they've definitely broken up," a source told People, adding, "The relationship had just run its course."
The pop star-turned-
"Jennifer is actually doing really well and working hard," the mag's source added.
"It wasn't an easy decision, but they decided to stay friends," another source told Us Weekly. "Their relationship couldn't work with the distance. He started trying to establish his own life and career, and she is so focused on hers, and they just couldn't be all about each other anymore."
The pair is said to have had an amicable split and remain friendly, despite growing apart, TMZ reported.
The break-up news comes on the heels of a messaging scandal implicating that Smart exchanged naked photos with a transgender woman on
"Casper has been a single guy and can text or see whoever he wants, but the idea that he was knowingly texting a transsexual is laughable," a source told TMZ. "He's not that guy, but like a lot of single guys online he obviously likes to look at a little ... "
The site said the former dancer is pursuing an acting career and is in the process of moving out of Lopez's house.
Meanwhile, Lopez is involved in a free summer concert series as she promotes her 10th album, "A.K.A."
The "First Love" singer returned to her home borough of the Bronx on Wednesday where she performed for the first time and resurrected her infamous 2000
Lopez, who is mom to 6-year-old twins Emme and Max, split with Marc Anthony in 2011 after eight years of marriage. She was previously engaged to Oscar-winner
Before that, she was married twice. First to Cuban actor Ojani Noa and then briefly to choreographer Cris Judd.
The "I Luh Ya Papi" singer addressed her trail of failed romances in the April issue of InStyle.
"Look, I don't love being alone. I don't. I can't beat myself up for that. What I have to do is figure out why I don't like it. Why am I not OK being alone? And can I ever be OK facing that?" Lopez told the mag.