Cougardad,
It gets more difficult now, and a few weeks after treatment. Your doctors start getting concerned when you lose more than 5% of your weight unitentionally, which can have a negative impact. Most of the weight loss is muscle, especially skeletal muscle, some fat too, but it may be hard to regain due the metabolic effects of cancer. I was about your weight, 245lbs in 2009 going into treatment, and went down to 120lbs in a months time due to cachexia. I've regained some weight, lost and gained again, and about 164lbs now.
Treating any mucucocitis, thrush, pain, dry mouth, mucous, nausea or vomiting, may make eating more tolerable, limit weight loss.
Marinol, a prescription medicine, can help with nausea, and help increase appetite, as well as caffeine, fat/sugar type foods, if you can tolerate it. There were times I just used the peg tube, and slept. Sleeping also helps with recovery. They say light exercise such as walking may help too to increase the appetite, clear the mind, but at times I couldn't even do that, but just remember, it does get better over time.
Good luck