Jennifer Lopez -- Breaks Down In Tears During Concert

Jennifer Lopez began crying on stage during a concert in Connecticut Saturday night ... after singing the "last song I wrote about love."

Lopez was performing at the Mohegan Sun casino ... when things became emotional and the singer -- who recently split from hubby #3 Marc Anthony -- began to tear up in front of the crowd.

Lopez had just finished performing an acoustic version of "If You Had My Love" ... when she reportedly told the crowd, "I'm going to sing you the last song I wrote about love ... a lot has changed since then."

Lopez then performed, "Until It Beats No More" ... which was originally released earlier this year, before she split from Anthony.