braveheart - I amnot so sure about the not wanting to hurt. I thought for a long time that the hurtful behaviour to the kids was a by-product of the situation, but having looked at it again, I can see a prety mean streak in all of it.
For example when his sons came to visit when we were packing up the family home he did not eat dinner with them the firs night, but with OW. In each case he hadn't seen them for more than 6 months.
I did raise it with him calmly at a later date, and tell him how much it had hurt them. He did not deny this. I think he knew what he was doing. One theory is that they are so miserable that they enjoy hurting others.
Ater all happy people try and avoid hurting others.