The Im Into You star took to the stage to sing some of her most famous hits for the son of a Ukrainian oil tycoon's nuptials, reportedly receiving a cool $1million for the gig.
According to US Weekly, Lopez stayed in a luxury $4,000-a-night hotel suite during her stint in the Ukraine, with staff telling the publication that despite her recent heartbreak, Jen was "very pleasant" and "smiled a lot."
It is thought that the On The Floor hitmaker even took the time to pose for pictures with fans, before heading off to the wedding venue to perform for 500 guests.
Once on stage, Jennifer apparently exclaimed: "Are you happy? I am happy, because I am here with you today!"