While he is away, it may be helpful that he engages in some self introspection to figure out what does he want both in the short and long term of their "relationship" He will need to examine this not only from his subjective view but in regard to how it would affect the children, his finances and his life in the future.
It would be helpful to have some professional counseling to assist him to sort his emotions and thoughts. You can encourage him to try and explore his options. If he is reacting based on emotions as you believe, he would need an objective person to help him sort through this. You are his mother and he may not see your view as totally objective. If he listens to you, then try to find out what are his plans for the future. He may be distracted and not think about the long term outcome of this situation.
Dear Dr Rossi
Thank you so much for replying so quickly. Yes, I agree with what you have suggested and have had conversations with him along these lines. Also he has had some personal counselling and they have been for couple counselling too, neither experiences have eld them very far. I'm looking for something formulaic (like a questionnaire or similar) that will kickstart the deeper thought process for him. I think that at the moment he is going round in mental circles and not making any progress. Is there anything like this out there - if you think this is a reasonable idea of course. Many thanks, Jenny
He can consult with a life coach (since he's already seen a therapist) Books can be helpful but it all comes down to his willingness to change. He can not change her nor anyone can change him. His level of introspection will determine what he does. He may benefit from talking to others in the similar situation he's in via online support groups.
As far as questionnaire, he can focus on the short and long term goals for himself. He can write these in a journal or jot some outlines and then think about these. What would being divorce mean? What are his responsibilities going to be to the children both emotional and financial? What would his life be as a bachelor with children? What factors led to the divorce or separation decision? Are these things that can be worked out or are these permanent road blocks in the marriage? What factors are keeping him stuck- fear, hope, does not want to seem as a failure, does not believe in divorce, etc.