Some options:
Fly from CVG to Atlantic City, NJ. You get a little bit of everything. There are of course the casinos with gambling and headliner entertainment and great dining, but there's also relaxing strolls on the boardwalk, and of course miles and miles of relaxing beach on the Atlantic Ocean.
Drive several hours north to Cleveland. The Rock and Roll Hall of Fame and Museum is about my favorite building in the country. You can easily spend 5 or 6 hours or more in there. Plus there are beaches on Lake Erie, plus great nightlife and dining, as well.
Look around on a generic B&B website for B&Bs about 2-3 hours' drive from where you live. It really doesn't matter where, it's just getting away without the kids, without little ones who are pulling on you every second, without lunches to make and chores to do, etc. My wife and I are getting away next weekend, for our 15th anniversary, to a B&B on the Chesapeake Bay about 3 hours from us. We have a 6 year old and a 3 year old, and we've gotten away without them only twice since they've been around. You really need to do it every now and then if you can, not just in reaction to a problem but to PREVENT problems.
Good luck.