Hi Tim,
I guess it depends on the type of cancer and the prognosis. It is life changing though for most I think.
Doing things you normally enjoy, does help, it takes the stress levels down, which helps you cope with the treatments too. Music is great!
I think you do get "used" to your diagnosis, but it takes time, it is a wake up call, though.
There is a balance between living a "normal" life and accepting life has changed, you can never go back to the pre-cancer "blissful ignorance", but it is much better to know (i) there is a battle to win & (ii) what the "enemy" is.
I hope you & your wife, manage to adjust to the news, get information and find some peace over Christmas and summer holiday.
This site is really good for the days when you just want to scream, coz we all remember the "shell shocked" feelings
Go well.
Sam