No, it’s not. I mean, you’re entitled to feel like you’re being selfish, of course, but I think looking after yourself is never selfish. And you’ve looked after the writers, too, by stepping down from a role you didn’t think you could handle at this time.
So please be kind to yourself. And please remember that, while I’m sure the writers are devastated by the news, you also gave them a gift when the call went out to apply—I read plenty of their comments talking about how they’d gone above and beyond and found new depths to their own writing, because of the challenge you set.
I wish you all the best with the coming weeks and months, with your goals and your needs and your health, and I look forward to reading more of your writing.