During Mullen's first marriage, she endured physical and mental abuse.

[4] In 1993, she married singer, songwriter and music producer David Mullen.

In a Facebook post, she cited "Biblical reasons" for the divorce.

[5] In 2016, it was reported that Nicole had entered into a relationship with minister and singer Donnie McClurkin.

[8] Mullen was inducted into the Christian Music Hall of Fame in 2011.