The Jack & Diane singer began dating former supermodel Christie last summer (15), but last week (09Aug16), the couple announced it had called time on the year-long romance, revealing their busy schedules had put a strain on the long-distance relationship.
The two stars vowed to remain the best of friends, and when New York Post columnist Richard Johnson suggested the couple had split because Christie had had enough of the rock star's "hellbent political opinions and his redneck ways", she jumped to her ex's defence.
She took to Instagram and took aim at the writer for the "convoluted article".
"While much has been written over the years about me that I simply allow to roll off my back... I do stand up for my friends when things seem unfair and this is the case here," she wrote.
When asked about her Instagram post at the weekend (ends13Jul16), Christie told Entertainment Tonight it was just a matter of loyalty and kindness for someone she will always care about.
"I just think that in today's world, with everything we see going on and all of that, it's really important to stress kindness," she explained. "I think we start in our own homes and our own circles and if you see a friend that's not being treated fairly, you stick up for your friends."
The ageless blonde beauty was then asked if there was any chance of a reconciliation with Mellencamp, and Christie vowed to never say never.
"You never know," Christie said. "Good friendship is the basis for everything, right?"