Wife told to stop cape. She feels a bit defeated. I don't think that's the case

Hello, your wife is very lucky to have you. Keep up the positive attitude it’s so important. My cancer was different and I am still having preventative treatment for next 8 months. I agree there is a perverse comfort in receiving the drugs and seeing your Drs, the structure of the visits and routine makes me feel calm. my cancer wasn’t seen or felt and suddenly one day I had a slightly inverted nipple and then 3 days later I had the news that I had cancer, would be having chemo and a mastectomy. I think it’s the fear that comes with how invisible this disease can be. 
Luckily I have had a full pathological result but as it’s HER2+ the drugs continue and this does make me feel secure. It may come back , who knows but for now it’s a great result and I know that my Drs are still seeing me and are checking. I would feel the same as your wife, wanting to fight for every % that each drug gives, I remember how clearly I realised I wanted to live when told I had cancer. The only thing that I can offer that may help is that my chemo had to be stopped due to my liver being very unhappy and I was worried that as I hadn’t had the full course and all cycles it wouldn’t work as well. My oncologist told me that he was happy with the amount I had had and I just had to accept that and go with it. For sure there was the feelings of “why can’t I cope with it”I always said I’d trust my Drs and they are the experts, so I continued to trust and following surgery the result was better than expected.I am sure with your continuing support life will become more normal and less about cancer, it just takes time and adjustment. 
Wishing you both well xx