I'm sorry to hear it.
Keep in touch with your contacts at AZD... it sounds like they are interested in colonizing, just not quite yet.
Things can turn around more quickly than you think. My AEPhi colony doubled from 11 to 22 members in a single rush - and it was formal rush, when we were there alongside 4 well-established national sororities, each with 70+ members. So, it can be done.
I'm curious - what happened to AZD's plan to do a colonization from the ground up, hold interviews, and take in most if not all of NBO's members along with however many unaffiliated women they'd need for a viable chapter?
After reading leilanimoon's rush thread, I'm wondering if it seems to the unaffiliated women at your school that you'll just take anyone for "body count" rather than being selective, and they're getting turned off by that perception. I haven't really gotten a sense for how selective NBO is... it's just something to keep in mind. Nor should you cut women just for the sake of cutting... it's a fine line to walk, especially when you're small.
Try having a COB rush week later this semester, and maybe another one after the holidays, and see where that gets you. It may also be time to reopen the search and look at sororities other than AZD again. Just a thought.
Take care.