Annem your pain will go in about 4 years. You WILL survive, promise.
He has another woman, and this was an exit affair. He has gone (but there is some ambivalence).
Now: what you have to do, is work on YOURSELF. Where does your depression come from? Your childhood? His treatment of you and your loneliness, or (probably) a mixture of the two?
I could have written your post. I was you, devastated. Now, 3+ years on he could walk out the door and I know I would be fine. Only, he won't go!
You have to be a little bit honest and look at your dependency on him. THIS is the 'me' work you need to do. Carry on going to counselling, and focus on YOU.
- Do you work?
- Do you have your own network of friends? (they are the ones who will support you and stop you being isolated, and let you know you are lovable)
- Do you have an activity that gets you out physically? Zumba class?
- Do you have a hobby or interest as part of a group? bird watching, rambling, quilting, whatever.
Until you have sorted out these things, your marriage and relationship is irrelevant. You MUST do these things, learn to stand on your own two feet. Otherwise you are a deadweight to him or any other man, can you see this?
This is very hard work, the hardest you will do. But when you do, your pain will recede, you will be doing what you should always have been: a person in your own right. How much more attractive are you to your H then! If you start this now, OW will have worn off, and you could maybe one day start again, this time better?