welcome to e.health forum. now to start with the good thing about this situation is and important one is you are aware of what is happening. the girls are the ones to keep an eye on as we all know its the vulnerable that suffer as did my own girls.
i would try and talk to them as they will be too scared to tell there mother.
is there anyway you can take them out for the day?
in situations like this as i found they are actually more aware than you know and they need to see you are on their side to support them.
mother in law as you mention is aware of what he is doing and therefore protected. i can,t understand why she is still with him to be honest because only she has the power to take the girls out of this unhealthy relationship?
the girls are lucky toi have you and you may just be surprised how they will open up to you.
i felt so guilty when my girls went through it and wish i had picked up on it sooner but i was not aware of what was happening.
keep us posted as we are here all the time to help and advise.
thoughts are with you.

thank you so much for your help, at the moment it is hard for her to leave him, and she doesnt realise that the girls have clicked on as such.
i will take up onur advice of taking them out and letting them open up to me, i feel the most important thing is that the girls have trust in talking to somebody about there feelings.
your advice is much appreciated

hello you are welcome. i hope things go well and im so glad the girls have you to turn too.
there shall be difficult times and if you need someone to talk to we are here.
private message me if you prefer or post here choice is yours as we are a great team on this forum.
keep in touch let us know how things are progressing my thoughts are with you.

In 'text book' cases of abuse, emotional abuse is the starting point. The abuser wants to be able to show he can reduce the victim to tears, that he can hurt her. When he is successful he continues until she no longer responds or he no longer gets the kick. This moves to intellectual abuse, where this situation has reached. After that comes spirtual, then verbal, then physical.

i was raised in an abusive household and you cant even imagine the effects it has on one's life.
the only thing you can do is be supportive. you mother-in-law has to make her mind that she's not going to live this way. you can throw positive suggestions at her in how she can leave him.

my mother has a habit of getting into one abusive relationship, leaning on her kids for help getting out. and this is a continuous cycle that is endless.