Well, the college needs to be told you can't afford it, and ... bluntly, you can't afford it, so they can go bark for it. Send them money when you can afford to. Try to talk to them about it. Social Security disability is really hard to get without a lawyer. My housemate who is schizophrenic and unable to work due to being unable to leave the house most days has been rejected twice. It truly sucks.
