I know what I have to do and I plan to do it. It's a good time to get it done and get it behind me. It's treatable, so why not treat it now? My family will give me comfort but I have to do this alone.
It all changed when I realized I'm not the only one on the planet who's scared. Everyone else is, too.
Deciding to write a novel about something - as opposed to finding you are writing a novel around something - sounds to me like a good evocation of writer's block.