I do wish you hadn't used AI to write the obituary, and I hope you won't use AI to write anything in the future, for reasons I've gone into in lots of other threads here. Generative AI tools like the one you used are unethical, based on theft of intellectual property.
They save you from having to think, but that is NOT a good thing for Homo sapiens. They're handy dumb-yourself-down tools.
And using them undercuts your credibility. If you used a chatbot to write an obituary, you might have used one to write all or part of your messages here. Last year I was discussing this with two teachers on Twitter who'd written books about using genAI, approving of its use, but had both also written fiction that they hoped to sell, and they were worried that agents and editors might not believe they'd written that fiction themselves (as they said they had) since they'd used AI for other types of writing. I had to tell them they were probably right about that. I've posted threads here about science fiction magazines that will permanently refuse submissions from anyone they catch trying to pass off AI-generated text as their own.
You wrote of using that chatbot:
I thought it did a lovely job and saved me the angst of trying to get it just right.
The same would have been true if you'd had someone else write it for you.
But for your own sake, your own feelings and your own coping with loss, it would have been best to write it yourself. As it is, you're feeling so defensive about it that you even brought it up here.
And feeling angst about writing something important is normal. It's what you should feel.
You can't undo having used AI for the obituary. But you can avoid using it in the future, so you don't disable your own ability to write and leave people wondering if you really wrote any text from you that they see.