Sorry, AT WILL means just that. Whatever reason they want or can think of. Supposedly they dont have to give you a reason if it is at will. Because they did give you a reason you may have recourse, but do you really want it. I think you deserve to work someplace that you would be appreciated. If they hired you to do a job and you were able to do it, what do they care what your disabilities are. And from what you said you told them initially! Dont know if you have a Walmart in your area. I dont really like the store but those are personal reasons. However I did work there several years ago and they were good to work for! You may want to try going there. They will more then likely be glad to give you the part time. I know things like this are very stressful. No one likes to feel like they have been treated unfairly. Take Care. I am sure you will be better off some where else!