Hi Evan,
As a loving husband I completely empathize with your position. My wife was in the same situation at the end of October of last year. Diagnosed with Stage IV colon cancer her prognosis was grim.
I decided that helping her had to be my main function. All else took a backseat throughout the radiation and chemotherapy. I made it my job to learn as much as possible about the drugs and solutions presented so that I could converse in an informed manner with her various doctors and nurses.
It was a decision I will never regret. So here is my suggestion.
Spend as much time as you can with your wife. Give her your shoulder and heart as much as you can. But...
When you start to feel torn between caring for her and keeping the home on sound footing, call one of her or your friends and ask for help. They really want to, and it helps her grow closer to them.
Most men are solution providers. We want to fix things. We seek the quickest way to that goal, but this goal cannot be reached by you alone, and not quickly. You need your "team".
Get a friend to mow the lawn (or whatever) when you need to spend time with your wife.
Get away when you find yourself getting angry with her (and you will), by calling one of her friends to spend some time caring for your wife. It WILL make things better.
Find things you can laugh out loud at. Your wife will laugh or smile with you and you will be refreshed.
Talk to your personal Dr. about your situation. He/she will be able to support you in ways you may not have considered.
Start a personal blog about your feelings. You don't have to make it public.
When your wife is recovering, forward the phone to your cell so that she can get some rest. Her friends and relatives will probably understand, and she won't be annoyed by solicitors.
When she can take care of herself, get back to work. It provides a chance to get your mind off her condition, not to mention helping the financial issues.
Make a list of your team members and keep it close. Keep in touch with these people the best way you can. They can be your salvation.
As the woman before me said,
"God bless you both and give you strength, courage, grace and a healthy sense of humor. Keep laughing!"