Hi petallus. No, ex-DIL's family are all still friendly but don't believe in getting involved. They all disappove of her behaviour, but fear her wrath, as she can get very nasty. They say they just want a quiet life. The older children (step-brothers and sisters) who my son was a step-father to, all like my son and one said to him 'I don't blame you for leaving, I don't know why you stayed as long as you did' when he told her he was packing to leave and would be renting a flat 500 yards away, so he could be near them. He continued to pay for her driving lessons and college fees, even though she was 18. He remains friendly with them all and will help them out every now and again, even though they are now all adults.
My grandson (12) knows a few things appropriate for his age, but he doesn't know the extent of his mother's abuse of my son. He has witnessed her being verbally abusive to him, and apparently told his other grandmother about this. She has always been friendly with me, but says to me 'you know me, I don't get involved. I just hope she doesn't keep it up too long.'
Ex-DIL did manage to shake off her ex and the older children's grandparents within a year or so of meeting my son, and she has behaved in the same way towards us.