Gone and done it and basically said I'll help you pack. When he started on the past poop I agreed that I played my part but said I saw things differently. He wants me to understand why he is doing this and give him my approval. He was crying and blubbing but I let him get on with it and resisted the imoulse to hug him.
So he's taken some stuff over to OW and I've packed as many clothes and things I can lay my hands on. Put it all in his room.
Will have to see what tomorrow brings. I just can't stand it any longer. Hope he takes the whole lot away, including himself.