I missed that the big tax bill passed at the end of 2017 contained a change that benefits some disabled individuals. You were already able to get a federal student loan discharged if you are disabled and Social Security had set a five to seven year re-examination date for you. However, the discharge of the debt was considered income to the disabled person which often meant that the discharge could cause an expensive tax liability, which defeats the purpose of giving the discharge in the first place. That was changed at the end of 2017 by 26 U.S.C. §108(f)(5)(A), which provides that the discharge of a student loan debt for this reason is not income. However, this sunsets after 2026 but I doubt it will be allowed to end then.
Unfortunately, the five to seven year re-examination date requirement limits the value of this. I don't know what the numbers are but I'm pretty sure that few who are found disabled by Social Security get a five to seven year re-examination date even though very few have a realistic hope of getting better. I don't know that there are any re-exam dates that long for any sort of mental illness other than profound brain injury.