In this counseling answer:
•Islam permits separation between a man and woman under all such circumstances where the man becomes abusive and is not willing to change.
•You need to family counseling and a treatment and management plan for your special needs children
•Ask him to help you and help himself and save himself and his family from ongoing unnecessary pain in this world and the in the life hereafter.
As-salamu `alaikum sister,
Obviously, you have been going through some trying times for quite a while. But, al-hamdu lillah, Allah Most High has given you good faith and the strength to bear and make the best of your circumstances.
It is clear from the details you have provided that your husband has not been psychologically and emotionally able to accept the fact that his children are not as he had expected. Although he is, otherwise, a good man, it seems that he, more than you, needs urgent psychological counseling to help him deal with his emotional disappointments and the resultant effects on his behavior and his marriage.
It is because of his disappointment in his children that he seems to be selfish and uncaring. But, notice that he also suffers from self-pity and a feeling of total helplessness. He has been suffering, but is dealing with his pain through verbal abuse of the children, and perhaps you, and by blaming others (including you and perhaps God for his fate).
Obviously, unlike yourself, he is not of strong faith, which is also adding to his lack of acceptance of his family situation, making him more miserable.
Should you separate from him? The answer to this question will depend on his willingness to seek help, followed by family counseling and a treatment and management plan for your special needs children. Although possible, this will be difficult through long distance counseling. You should find some local therapeutic resources that can meet all these treatment and counseling needs.
In the event he refuses to seek help or to assist you in the treatment and management of the children, you may have little choice but to consider other options exclusive to him.
Now to the question whether Islam permits separation between a man and woman under these circumstances. The answer is that Islam permits separation between a man and woman under all such circumstances where the man becomes abusive and is not willing to change.
Check out this counseling video
Ask him to help you
My last piece of advice to you is to show him your question and my answer to it. See how he reacts. Beg him to help you and help himself and save himself and his family from ongoing unnecessary pain in this world and the in the life hereafter. Ask him to write to me if he needs to raise any further questions about what I have said.
I pray for all of you. May Allah Most High give you strength and protect you from all unnecessary pain.
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