Milian, 32, and Prince, the CEO of Rap-A-Lot Records, had been engaged since May 2013.
"It's a really good thing for her," a source says of the split, adding that the now-single singer spent time this weekend with girlfriends by the pool at the SLS Hotel.
Reps for the singer did not respond to requests for comment.
Milian played coy about the date and wedding planning in an interview with PEOPLE in April, saying it was Prince who was asking her to nail down the specifics of their nuptials.
"He's bugging me every day like, 'What are we going to do? What's the date?' And I'm like, 'I don't know! We'll figure it out,' " Milian told PEOPLE, noting the fun she was having looking at wedding inspiration photos on Pinterest.
Although Milian has stayed mum on the breakup, she may have hinted at the split on her social media. After a "rough day," she cuddled her newborn niece in a photo on Instagram. In a separate post, she uploaded an inspirational message, which read, "There comes a time in life, when you walk away from all the drama and people who create it."
Prince also left a clue that he was moving ahead by faith, posting Thursday on his own Instagram account: "Keep calm, pray and leave it all in God's hands."
Milian, who served as a social media correspondent on The Voice and appeared on season 17 of Dancing with the Stars, was married to singer The-Dream in 2009. They were later divorced in 2011 and now share custody of daughter Violet, 4.
Reporting by MELODY CHIU