Wendy, You need help from your medical team immediately! Stopping treatment is not an option. Someone has to take over your care for awhile. This is not a matter of you not being strong enough. It's a severe reaction to treatment with dehydration and weight loss.

Don't you get evaluated prior to radiation daily? Haven't the MD, Physician Assistants, and nurses on the cancer team established a relationship with you? All the things Christine and others have written need to be considered - hydration, medication evaluation, Peg or nasal gastric tube, etc., but FIRST you need a through medical evaluation

I do not think you can wait another day to get help. Your medical team needs to make a plan for you to be able to complete treatment.