I couldn't eat or sleep either. I lost about 12 kgs down to 52 kgs and look like a skeleton. Every time I turned my back my H talked to the OW. Like you I argued and tried to pressure my H to come back to me. Now I have changed and I am not the same as before. I have noticed the DB techniques working slowly but surely.
Once reading this page you'll discover that you are not using DB techniques right now. Remember no arguing, everything your H does and says is perfectly ok, because you love him unconditionally, also remember no pressure and that means no asking him to end his EA/PA no telling him to go to therapy. If he don't want to talk to you say 'yes ok I understand' and leave it at that. Remember H will never ever forgive himself for what he's done and when he says this say 'Yes I understand that you can never forgive yourself' be sincere and leave it at that. Remember small talk, happy talk. What your doing now isn't working, so change. Do something for yourself. Your H will never go to therapy so forget it. Any pressure to do stuff will just drive him away. Be like you are easy going, happy, relaxed, and you'd prefer to live life with your H, but you don't have to. Don't deny there is a world out there beside your H. Do this and he'll start to remember the person he fell in love with. I contacted old friends to remind me what I was like before I got married and it really helped. Your H is not going to do anything differently right now only you can do things differently.
Like you I was living a nightmare, which I thought I would never wake up from, but have since discovered that you can wake up.
You have to decide if you still want to be with your H, which you didn't mention. What about you? What do you want? Your letters reflect that your reacting to your H and his PA/EA. It sounds like you want him to choose you over her, you love him, but you don't really want to continue your relationship with him.
