Views along the way

I would stop in Baltimore, Washington DC and or Charlotte. These are the top things to do in each of the cities:

• Baltimore - Inner Harbor (museums and restaurants) and Fort McHenry National Monument & Historic Shrine
• Washington, DC - National Mall, the Smithsonian Museums, the White House, Capitol Hill, Lincoln Memorial
• Charlotte - Nascar Hall of Fame, Billy Graham Library, Carolina Aviation Museum

Personally, I would drive around New York City and get down toward Philadelphia as soon as you can on the first day (or early on the second day). That's a long drive, but it'll be a lot more interesting from there.
Stop by Atlantic City if you like to gamble, though it's no Vegas. But the main thing is get to the coast if you can. Assuming you and your boyfriend like beaches and you're on a budget, there are so many places you can stop.
Start at Virginia Beach if you want, or take a little time to see the Outer Banks like Kitty Hawk. Just make sure you aren't crossing the bridge on a Saturday during peak season, it's backed up for miles.
Drive down to Wilmington, a nice small town on the ocean, and Myrtle Beach, then cross back over toward Atlanta.
If you can spare even more time, try to get to Hilton Head Island or Tybee Island before you end your trip.