Hi all,
I have been lurking for a while, reading through other people's experiences and wondering whether to post...
DH has recently decided to go nc with his mother, my MIL.
There's a back story, which is almost 11 years long, so I'll spare the details if people don't mind! 
The short version is that after living with us (me, DH and DD) for 11 years full time (court order etc) my DSD has decided to move 80 miles away to live with her mum.
A great deal of upset has ensued as DSD decided to move out of the blue, and basically went for a holiday to her mums and refused to come home to us.
Cue, MIL, who is very supportive and makes herself indispensable by providing lots of child are, for DSD, less so for DD.
This scenario has opened the mother of all cans of worms!
Ranging from MIL calling DH a shit dad for letting DSD go, to saying that I am pure evil and a controlling bitch and I'm glad DSD has moved (I'm gutted about it, I've been her full time mum for the past 11 years!).
I've never really thought about it before, but MIL is a total control freak, particularly around DH.
and if DH doesn't 'comply' with what she says she will;
A) question his parenting
B) threaten to cut us out of the will
C) threaten to withdraw child care support
D) say 'your father would be so ashamed of you, he'll be turning in his grave' to DH (DH adored his father, he was a wonderful man and questioning the bond between them really rattles DH. He's told MIL this but she takes no notice)
The day we were due to move into our first house, ten years ago, she purposely gave the garage key to DFIL so we couldn't have access to the car to put a mattress in the house to sleep on for our first night. We called a cab and asked them to help us shift the mattress, she then screamed and shouted at me in the street and said to DH 'she's taking you and DSD away from me!' We moved half a mile down the road 
The list hoes on and on. All through DH's childhood, he was encouraged to be attached to her apron strings. She would put him down, tell him he couldn't do things and it would make him gravitate towards her.
Needless to say, he has suffered with major self esteem issues all his life, seeks constant reassurance and when he doesn't get it he gets angry. He has had 18months of CAT therapy after a breakdown 2 years ago and things were just settling down when DSD left and it all started again.
We have been nc for about two weeks with both MIL and DSD (at DH's insistence as it's clear that DSD is manipulating him the same way MIL does unfortunately, that's a whole other post!).
The difference in his MHealth and general we'll being is unbelievable!
Sorry it's a massive outpouring of emotions, but just can't believe other people have been going through similar stuff, I though we were the only ones!
Thankfully MIL is due to move house to be closer to DSD in two weeks to the nc will be much easier, she currently lives about 100 metres from our house.
DD has been nc with MIL as long as me, which is coming up for 2 months.