So sorry. My DW is the same age as yours and is going through breast cancer treatment for the second time. My only advice is non-financial, which is to seek support and help for yourself. I was amazed at how zero was offered to me, the spouse and caregiver, even while such excellent focus is given to the patient, where most of the energy is naturally and correctly directed. Not one single professional offered counseling assistance to me, and this was at a top flight breast cancer center. Nevertheless, as someone walking through hell, you really need a support group or fellow traveler or expert to lean on. For example, even though I do all I can to help and I attend virtually all doctors' appointments and surgeries, I was feeling growing guilt about a recurring, involuntary fantasy of forming a new life on a Caribbean island should DW not make it, which I obviously did not share with DW or anyone we knew lest I seemed to be selfish. A counselor I sought out myself told me that my reaction was alright. My fantasy was just a coping mechanism and my natural fight or flight response protecting me. That helped me make sense of my internal process and neutralize guilt, which let me focus on my wife better, whom we think will be OK. Anyway, my point is that I hope you can get some support for yourself if you don't have it, because I found that it's rather critical to do and not something a guy should try to tough out, as is often our default mode, and I wish you peace and comfort in this extremely hard time.