Seems you have a very supportive family network, probably friends too. Keep them close, you will need them over the coming weeks/months . . . it will seem like a long time but, believe me, it isn't. Just concentrate on getting better and I guess everyone here joins me in that one.
This is a wonderful site if you need info, just need to vent/get support etc. There is always someone who has been through something similar and can understand what you are going through [although I am very envious of the reconstruction bit!!!]. Like you I was 'gob-smacked' but, thankfully I had a friend with me who had been through it 13 years before. I know things have changed tremendously in that time but just having her there was fantastic and I couldn't have done it without her.
I guess what I'm saying is this diagnosis brings home the fact that all of us should enjoy the little things in life [like our kids, a cuppa etc] so here's hoping all goes well for you, sending healing thoughts your way and keep positive :)