Michael,
I think it would be helpful for Seth to familiarize himself with this site. There are many caregivers who post here regularly and can offer a great deal of advice and support. Without a doubt, being a caregiver in this situation can be very stressful and frustrating, and there are resources here that can help to alleviate the pressure. I would also recommend that some of your other family members log on here to get a fuller understanding of this disease and the treatment options.
I have to agree wholeheartedly with Barb's post above where she advises against "saving" something for a recurrence. My cancer team pushed to do everything possible on the first go-around, as my tumor was showing signs of aggressiveness. The surgeon removed many lymph nodes during the neck dissection/partial glossectomy (fortunately, biopsies of the nodes proved 100% negative for cancer), and I then had 7 weeks of radiation followed by brachytherapy. None of my doctors wanted to be in the position down the road of knowing that they could've/should've doing something sooner. After 16 years without a recurrence, I certainly can't second-guess their decisions.
Cathy