No Contact by DIL's?

Visited Mumsnet from email link and noticed a discussion about MIL's, it was alarming! It was full of hate speech about MIL's and many mums talked about NC. it means 'No Contact'; they deny contact to their children by their MIL's, they seem very self-righteous about this, comments like 'NC 5 years'. It's like a weapon they have and use. Have any of you experienced NC from DIL's? I hope not and I hope it is very rare. What do you think of this? Am I just late to this party? so sorry if this has been discussed before.