Hi Mad world
You have every reason to have a whole host of emotions. I have had a couple of lightbulb moments on my journey, the one I urge you to consider is this:-
I run a lot, I was listening to Julian Lennon, Saltwater. There is a line that says "what will I think of me the day that I die". I heard that when I was just finishing chemo and I thought, you know, on my death bed, whenever that may be, I can not look back on my life'post cancer and say to myself that I wasted a day. That for me is enough to get me doing all sorts regardless of how I really feel. Whenever I feel sad or as you say lazy, that thought comes into my head and makes me go for it, whatever it may actually be It that day.
I hope no one hasn't regrets after the epiphany that cancer can bring, life's too short.
Take care, dream like you have forever, live like this day is your last.
Kev