It took me a long time to come to terms with it, but what sealed the deal was that I could not possibly live the way I do in NY on my current salary. My rent is relatively high for DC but I live alone in a big apartment in a great location and would be living in Queens (no knocks on Queens, I grew up there) or a closet in Manhattan for the same price. The nicest restaurants are much more accessible and affordable in DC than in NY. Of course all this talk of affording a high quality of life means nothing because next year I'll be a po' student.
I totally get that. My COL is CHEAP in DC (<600/mo for rent), and I can afford lots of nice things since I live here. But I have no problem living a starting a really scrappy life in NY because the difference there is that I can DO lots of fun things, rather than have nice things to pass the time. I used to share a 1 bedroom with 3 other guys in union square, and I had way more fun with life doing that than living in a big townhouse in a quieter city. Granted, there are a ton of intangibles, like family and a built in network of friends in the NY area.
I definitely went through a rough time justifying the cost of NYC given how cheap life is in the DC area, but in the end for me happiness reigns supreme. That, and yeah, no matter where we go we'll be poor students