So sorry for what you are going thru. I am putting any blame on you what soever.
I think you should separate from your H and work on taking care of you, to make you whole again.
As much as your H is understanding, he is not a saint. He has wants and needs. He does not want to force this on you because in the end what does that make him be?
He is trying to work with you and that is changing him. When you told him to go outside of the marriage, you have made him into a cheater. Even if you gave him permission, he is probably not the kind of man to do this. You are forcing him into a position he might not have wanted to be. Thereby, changing the basis of who he is. He will do it for you, to remove the pressure of sex from you. But what does it do to him.
That's is why I am saying to leave your marriage and work on you. After working on you and you are healed, then, you can approach another sexually relationship.
Have an honest conversation with your H. With no expectations to resolve this issue but to find out how he feels and put out your feelings for him to see.
I wish you luck and happiness.