subletter woes

So, when I move to New York for a month in the summer, I need to have a place to live. I have found a lovely sublet, a teacher who is going travelling, but it is only for a month. And she's not quite sure of the dates. And she wanted half of the money up front as a deposit before she would take the listing off craigslist. I gave her the money, after talking to her several times, and she said she'd get back to me within a week with her final dates of travel. That was a month ago. So, today, I sent her an email asking if she'd nailed down the dates yet (because hey, she's got a lot of my money, and disappearing for a month after taking it and saying she'd get back to me was making me a little nervous.) I just got an email back from her saying "I know you just think I forgot about you or am trying to take your money and run. You don't have to panic. I didn't forget. But I don't have final dates yet- I'll get back to you." So now, in addition to not knowing when this sublet is, exactly, I feel all defensive about my decision to follow up over email. Am I being anal retentive? Panicky? A nitwit? Or is this something about New Yorkers that I'm going to have to get used to, this scorn for all people who live outside of Manhattan?