Keyshia Cole & 'Boobie' Gibson -- Hugged Up At L.A. Party ... Reunited?

One of the most bitter celeb breakups in recent memory might be on the mend 'cause R&B star Keyshia Cole and her estranged hubby Daniel "Boobie" Gibson were out together in L.A. Monday night ... looking pretty cozy.

Keyshia and the ex-NBA star were spotted at the premiere of Keyshia Cole's new reality show "All In" and seemed to be enjoying each other's company.

Daniel even Instagram'd a pic of the couple(?) hugged up together with a very affectionate caption that read ... "Look what I found ... full support of this Angel at her premiere."

It's a fairly shocking development considering the split was public and nasty with Keyshia previously telling TMZ Sports that Gibson had turned her off from athletes forever.

Despite the bad blood ... the two never officially divorced, making for a much smoother ride to that town called Reconciliationville.