PLEASE!!! Contact the ALS Association
http://www.alsa.org/ or the MDA ALS division
http://www.als-mda.org/disease/als.html They can help you understand this more, provide help with medications and medical hardware such as beds and wheelchairs when needed. If your Mom isn't already on it, get her signed up for Social Security and Medicade ASAP. The process is a pain in the butt so you need to jump on it right away, I doubt she will be turned down with this diagnoses.
There are many different forms of ALS. Some folks loose their ability to talk, some the ability to walk, others the ability to use their arms. My very bestest, bestest, bestest friend, Tom, was diagnosed with ALS less than a year after his only son was born. Tom first lost his ability to walk, then stand, then his arms, and so on. It wasn't until just few hours before his death did he loose his ability to speak. From then on he communicated with us by moving his eyebrows, 1 for no, 2 for yes. Even when his breathing changed on the verge of death, I asked him if he was ok, and he responded with 2 lifts of the eyebrow that he was. I sat at the foot of his bed with the rest of his family as he slipped away.
Please don't give up hope so soon. Although there is no cure for this hideous disease, there are treatments that can help people live longer than they did when Lou Gehrig was diagnosed. Contact the ALS Association and get ALL the info you can.
Prayers coming for all of you