GM, I know from experience this view that 'nothing is wrong with them', as they wreck the lives of others, and hurt those around them.
I also know that counsellors are not easily fooled. My xh marched off with me to a counsellor, convinced that the therapist was going to confirm all he said. The therapist gently questioned my xh, who then left abruptly, and I didn't see him again for a long time. It would well be beneficial for your boys, and even your h. Just because you do not agree with what you believe are his reasons (and I am not questioning whether or not this is true although having dealt with a very difficult MLCer, can well believe this is exactly how it seems)doesn't make it a bad idea.
In fact I would agree with KD, their very certainty is suspect. They cannot entertain the idea that they could be wrong about anything, becaue so many MLCers create a false reality in which we, the family and the marriage are teh reasons why they are not happy.
Now, I don't know about you, but if I was in a situation where I wasn't happy (i.e. a relationship) I wouldnt go to another relationship.
If I felt my car was making me unhappy I would question whether I needed a car, not just sell it and get another, to put it simply. Nothing about MLC makes any sense to us, but it has to to them.