You need a consumer lawyer who has decided to focus their law practice on student loan litigation. You should be able to find one at www.naca.net. If you can't find such a lawyer close to you, give Joshua Cohen in Connecticut at 860-233-0338 x1 or look him up at www.thestudentloanlawyer.com. Good luck
You may contact Luke Wallace at Humphreys Wallace Humphreys P.C. at 918-747-5300 or Luke@HWH-LAW.com. For more information see www.HWH-LAW.com. The response above is general legal and business analysis. It is not "legal advice" but analysis, and different lawyers may analyze this matter differently, especially if there are additional facts not reflected in the question. I am not your attorney until retained by a written retainer agreement signed by both of us. I am only licensed in Oklahoma. See also avvo.com terms and conditions incorporated as if they were reprinted here.
The biggest stranglehold in my practice is exactly what you described. Federal loans have many great programs to assist borrowers, so even though I can (usually) can't discharge them in bankruptcy, I am able to work with them and get my clients on a payment that they can afford. Private loans are also generally non-dischargeable, but with none of the federal protections. Having co-signers makes it even worse (as they can go after everybody). I have tried to negotiate with them and lately have even allowed them to charge off and go to collections so that I have more settlement leverage with a third party. I wish I had a solid answer for you, but I agree with the previous post; you are going to need a specialist to advise you further.