Only person that comes close to a rival for me is CORN Wulfgang-Mello. We've met in two grandfinals for MK9 (Youmacon 2011 and Michigan Masters 2012), played several casual sets and have knocked each other out of Injustice ranbats.
I lost my rival, my friend that played raven quit getting better so i don't lose to him anymore, and my closest rivals after that are random clan members online like myztery_sauce khaotic smoke and emperor shaolin. Injustice kind of lost its spark with me, it reminds me why I don't play games competitively anymore, there is no point if your home town has no scene. I need a new rival lol