Josh --
You will not be able to resolve this alone. Once it's gone to the garnishment stage, you need someone to help you reorganize this.
Below is one company that can help you "fix" this; there many other companies.
There will be fees associated with this process and there will be an outrageous interest rate for a time.... but if you make regular payments on time, these companies do report to the credit reporting agencies and your credit rating will rise accordingly.
Student Loan Garnishment - Asgard Financial Services