Just in case anyone was wondering, I am going through with creating a local sorority since I just don't feel like fighting with the board of visitors and the dean about why they don't like greeks. I also joined up with another girl who is more enthusiastic about starting a sorority. My friend was just too caught up in boy drama. So far we've established almost everything and we're working on the constitution. It's so hard but so exciting. Any advice would be appreciated! :)

If you choose not to follow the local sorority route (even if you do, maybe), I'd suggest looking for local Alumnae Panhellenic groups, graduate chapters, fraternity/sorority alumni associations, etc. near your campus. There may be some local fraternity/sorority members who support your university and may be willing to put some pressure on the administration (in exchange for financial support).

And to revisit the subject, a public institution cannot restrict the type of organizations that form on its campus. I'll see if I can locate some case law to help you out, but in general, the campus is violating the right to freely associate. So long as your organization has an expressive interest and is not conducting illegal activity, there should be no reason they should forbid you, especially considering you have student interest.