OP, while one of you in school in DC while the other is in Philly or Philly while the other is in NYC is doable, I did a semester in NYC while my husband (then boyfriend) was still at home in Philly and it was hard. It was far from impossible, but I just missed him too much. I wasn't happy.
Here's all I would suggest. You are both juniors, right? Are you both planning on applying later this year to start medical school in 2012? If so, I would really suggest you start laying out a studying plan for the MCAT and get crackin'. If you could manage a 33+ on it, I think it would do a lot to offset a below average GPA. I'm assuming both of you have decent ECs.
Disclaimer: My comments about where the OP might have a shot are based on solely MCAT and GPA from my 2008-2009 MSAR, which is obviously a little out of date. Also, if I'm missing a school, or someone has a reason why any of these schools are a poor choice (big IS preference or something), please feel free to point it out.
Most of the schools in New York City are pretty competitive, stats-wise. That said, you have a decent shot at NYMC, which as a PP said, is 25 miles north of NYC in Valhalla, NY. There is also SUNY Downstate, in Brooklyn, UMDNJ-NJMS in Newark, and maybe Stony Brook in Long Island, as well as NYCOM and Touro-COM.
In Chicago, there are certainly more competitive schools like Pritzker and Northwestern. And for you, you have a good chance at Rosalind Franklin, Loyola, Rush, CCOM, and maybe University of Illinois Chicago (though they appear to really favor IS students).
I also definitely think you guys should apply to the schools in Philadelphia, where you would have a shot at PCOM, Drexel, Temple and possibly Jefferson, depending on how well you do on the MCAT. There is also UMDNJ-SOM which is New Jersey's Osteopathic school, in South Jersey, and Cooper Medical School of Ryder University is supposed to accept its first class this coming year. It will be in Camden, which is right across the river from Philadelphia.
Also, I would talk to your boyfriend about what schools he's interested in. You never know. Maybe he's interested in a school that's the only one in the area, but it might be a place where your stats are competitive, too. If that's the case for any schools, I would suggest you apply to them.
Also, as others have suggested, if you get engaged, schools may be slightly more inclined to give you an interview, especially if your fiance is already accepted. Schools want to accept students who they think will actually attend the school.
And really, school suggestions aside, it doesn't cost much to just get married by a Justice of the Peace and get a marriage license. A big wedding ceremony and reception is fun and all, but it's also a metric crapton of money and a LOT of stress. There're also a lot of options that fall between a JoP and a massive wedding party. You could have a tiny destination wedding, which doubles as a honeymoon. You could get married in a park or other public venue, or something small at a bed and breakfast, or even a nice restaurant, etc. You won't be any less married than someone that spent $40,000 on a 500-guest shindig at the Hilton.
Good luck.