It took Charlie a good 3 months before he started to feel better. Like your father he slept most of the time- but thier body needs to heal. What his oncologist said really was truthful "I put you into Hell and now its time to get out". Is your father in alot of pain? Does it hurt when he swallows? What is he drinking? I found that Carnation Instant Breakfast with whole milk were alot better with Charlie than Ensure and Boost. If he requires so much help- getting a aide isnt a bad idea because you need to rest from this too.
As a caregivers I know that I wanted Charlie to feel better so I would stop being so scared. His pain, weight loss(35lbs also), and sleep scared me and I felt alone because there was nothing that I could do to make him get better sooner. Please remember that me and everyone else on this site will be here for you.