Try to carry on as per usual, get out and about doing the things you love as much as you can. If any grace is to be found in such a bad situation, it is that you will value your own life more and make better use of it. Help him and your family as much as you can, you will regret it if you don't. Understand that he will have good and bad days, particularly if he has chemo or radiotherapy treatment. Overall, be positive, he wants to see you happy and productive, keeping yourself in good trim is the best way to help him. I'm not davey, but sadly im well qualified to give advice on this matter