Dealing with the Looming Cloud of the Possibility of Early Death

Five years ago, I had breast cancer. To rid myself of it, I had chemotherapy, radiation and a double mastectomy.
Flash forward five years. One day, I noticed a strange, bright red splotch on my breast, the breast where the cancer had been. The doctor did a biopsy of it, and the results came back malignant. It was an angiosarcoma, and the suspected cause was the radiation treatment I’d had five years before. This was a very rare form of cancer that, again, results sometimes from the radiation itself. That which was meant to heal me, made me ill.
On June 10, 2016, I had surgery to remove the cancer.
Fine and dandy. They got clean margins. Then, something awful happened. I was told that I had to have a CT scan to see if the cancer had spread throughout my body. (Nobody told me this beforehand.)
Enter fear, despair and disappointment. Enter the possibility of cancer and, therefore, the possibility of early death.
How am I dealing with this looming cloud of grief that is hanging over my head?
Below are some of my most useful techniques.

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