Cause: Just your classic martial demise, except this involved one of the greatest rappers of all time and his also famous wife. Their official divorce documents cited "irreconcilable differences," which likely refers to Nas's now public infidelity.
As a result, Nas got stuck with some pretty serious child support payments. The once insanely high monthly fee of $40,000 got cut in half, but that's still a decent chunk of change being taken from Mr. Jones every month.
Currently: It seems as if the former lovers have somewhat reconciled their differences. Nas's excellent "Bye Baby," along with really summarizing their whole relationship on Life Is Good, gives the impression that they have more or less settled their problems.