There's no easy answer. We all have to decide for ourselves what we think we can handle. I went with the advice of both my surgeon and oncologist - lumpectomy, chemo, radiation, hormone therapy.
Surgery was perfectly easy, no probs. Chemo was not fun but I suffered less side effects than many and I survived it, radiation was a piece of cake with no bad burns, hormone therapy so far is ok with only a few irritating side effects.
On the whole I wouldn't change a thing and if I have to do it again I will. My mum was 96 when she died and I hope to get close to that. I want to see my children's children, I want to be around for them. I am putting my faith in the brilliance of science and the advice of medical minds much brighter than mine. Who knows, in years to come they may find the magic bullet that cures us. I'd like to be around for that.
Ultimately you have to be content with YOUR decision. It's your body.
good luck
magicmum