runner, that's a tough question to answer because most of us don't have a valid reason for being panicky and anxious , we have just usually been under alot of stress and kind of snapped and began to let our minds run away with us. But your situation is different there really is a serious issue that you're dealing with, so of course you are going to think about it, be concerned about your wife etc. I think the difference is in what way your are thinking about it. You are thinking about all of it in a very negative way that is making you depressed and anxious. You should write down your thoughts in a journal, for instance if you are thinking, I just can't handle this, the person I love the most is really ill and the cancer could come back and she could die, so therefore I would be alone and I would never survive all by myself.
You replace that thought in your journal with, Bad things happen in this life, but I am very fortunate because my wife is getting better and the doctors have said the cancer is gone. I am going to trust what they have told me, and focus on taking care of her right now and not worry about the what ifs.
So by doing it this way you aren't avoiding the 'real' situations in your life, but you are keeping them in perspective and not allowing your mind to dwell on the worse case scenario.
