Perhaps those kids you were talking to were including grad/med/business/law school into their figures, since the real NYU avg for UNDERGRADS is $33,637.
It is NOT typical to graduate as an undergrad with that much debt. The few that do likely have parents that will be PAYING for some of that debt.
Seriously, you really cannot afford this school. What will your likely career be? How much will you be earning upon graduation? you also can't depend on finding co-signers for each of your 4 years. Being a co-signer is a huge responsibility. If you can't pay, then they have to pay.
Are you in-state for Indiana? Did you get any merit awards from any IN schools? What will your major be?