It's a question that every writer has to deal with.

You can write under a fake name and change enough details so that the folks you don't want to upset won't recognize themselves.

You can refrain from writing about it at all.

Or you can tell the truth and figure that if they don't want to be upset by it, they don't have to read it.

https://medium.com/ask-an-editor/what-did-i-do-when-i-learned-that-the-man-id-loved-and-trusted-for-20-years-had-a-secret-e3ee3e6a6510?sk=5a89c6b29c6bee37e29b07eabcf0504d