While it may be possible to have the loan discharged due to disability, it CAN'T be done as part of a bankruptcy without an adversary hearing. That's what you need to discuss with your attorney. The holder of the loan gets to say why it shouldn't be discharged. The trustee gave them part of the money just like any other creditor.
If your attorney isn't familiar with student loan discharges and bankruptcy, I suggest you might like to find another.
You may be able to find out about having the loan discharged without going through bankruptcy court by visiting this website: http://www.ombudsman.ed.gov/cancellation.html