My son separated from his partner, probably about a year ago.
They have a son, my grandson, who is eight.
He has two vocabularies.
One with his mum, where he speaks as she does, which is effing and blinding, and one with his dad where he speaks without expletives, and when he does let one slip out, it is quickly followed by a “Sorry daddy”.
My son has worked very hard to get my grandson to understand that using expletives isn’t something that everyone likes, and I am so proud of him for persisting in doing this, especially as he only has him for two days a week.
Swearing is a personal choice and, tbh, I use language at work I wouldn’t use at home or in front of strangers or children.