Teresa Dear,
You have the strength already, you may not just be realzing it just yet with the whirlwind of your other emotions.
The beginning was probably one of the toughest for me. We were sucker punched. If you asked me just a measly 3 years ago, I would not think in a million years that my Father would get dx with LC.
The way I found my "strength" in the beginning was to research as much as I could - from second opinions to what kind of vitamins may be helpful. Researching and gaining that knowledge made me feel proactive. I did even more research when the cancer started to progress. As a result, I was able to ask doctors informed questions and talk about other viable treatment options.
Once everything "normalizes" something similar to a game plan will evolve. And it will just be one appointment at the time, one task at a time, and one day at a time.
Give yourself some credit. I know that you feel selfish - but I really don't think that you are.
Shirley