He has 18 months to go in the Army and if her H gets wind of this he will inform them what is going on the implications of which for my H as the senior rank are incredibly serious, reduced rank, reduced pension or worse and I feel I need to protect him
You need to protect YOU and the children. He's almost 40! He can protect himself. That's why Cadet suggested seeing a lawyer. By my count, that's at least 3 times he's put himself and this BS before his own kids, so you know his words are worthless.
It may not be easy, but try to find a lawyer that has experience in military divorces and even better, those involving military affairs. I have a friend who went through this in the US, and you have a tremendous advantage should it head to D. She basically gave her XH 2 choices, the "easy" way and the "hard" way. He chose the easy way. She protected herself and her children.
That being said, I'm not suggesting you divorce. But I am suggesting that he needs to understand the serious consequences to what he is doing.
