I had to give my financial information to the college to see what I could help pay why does the non-custodial father not have to help also? Why in Georgia does child support stop at 18 and not 21 if the child is in college full time?

Because the law is written that way. The time to have done something about this was during the divorce hearings. You should have pushed for more. You may not have gotten it, but once you accepted the divorce settlement there is little you can do to change it.