It's not uncommon. My cousin sent out a Christmas card announcing her divorce - I think it stops a lot of 1-1 conversations with people which can be quite draining when you're already pretty raw.

What is the alternative to announcing a divorce? Keeping it secret? Not using social media to communicate?

In this case she explicitly did NOT make any mention of the divorce on social media when her husband first sprung it on her, nor during the process. She wrote this piece after it had been finalized.

She was unable "see" the divorce coming. That is one of the key sentences, therefore the need to explicitly announce the intention.

The actual post in TFA was actually much less weird than I expected from a "divorce announcement".

People looking for emotional support from friends and family during an emotionally draining event?

Divorcees.

Did you read the article?

...on instagram