No matter where I live, I will always be a small town girl from the upper midwest, a place that is known for its natural beauty. Suburbs? Hardly! And the closest city is a few hours away. So if someone asks where I grew up, I say Northern Michigan. If they know the area I can get more specific.
Now I live in Central NJ. I don't tell people I live in NYC or Newark. I just say central NJ. If people need an idea as to where I live, I say I'm about 30 miles from the Jersey Shore. Most people seem to know where that is. 
When my NYC friends rag on me about being in the dreaded suburbs, I just remind them that my family lived in Manhattan a couple of centuries before theirs did!
A friend's girlfriend is from Central Jersey and they rib her because "There is no such place.There is North Jersey and South Jersey, pick one."

When we first met they were teasing her and asked me, not knowing the joke, if there is such a thing as Central Jersey, and I said yes and named her town as being there. It's just friendly teasing, though, of the kind that makes for conversation as opposed to making it uncomfortable. And, hey, we're all from Jersey, so we're used to it.

Yeah, i'm lookin' at you, Willy Nilly!! LOL.
StareDecisis, welcome aboard. I think if you were going to say something for your friend a good time might be before you go on another trip. That may make it less apropos of nothing since it has been a while now, as you mentioned. There are some good replies already, and total strangers not needing to know the exact location of where you live is a good point. I am also a fan of asking someone why they do a particular thing, although if your friend thinks she is better for living in City i guess that could get pretty uncomfortable

I wish you luck; it would drive me crazy, too.