"We had a written agreement that during the S we wouldnt' date."
Okay, maybe I'm missing something here, but if a spouse cheats while they are married and living with you, why on earth would they honor some written agreement that they wouldn't date during separation? That makes no sense to me....
I EXPECT spouse, who has cheated, and who wants to be seperated, to date others. In fact, I'd encourage him to date.. not just OW but go out and sow those darn oats!!!! Get that out of his system. Why on earth should he limit himself to OW???
Rather then making him lie about this, I would tell him that because you are separated you both should be able to date... even if you don't plan to. He doesn't need to know this. Although, you can say, "No I don't plan to date, but I don't want to close off my options either...."
At this point, I don't think you have anything to lose. You have been traveling down the "cheeseless tunnel" too long. I truly believe your husband won't be anywhere near making a decision to stay or leave until he's spent enough time "examining the grass on the other side of the fence."
The longer you hang on or try to convince him otherwise, the longer you'll deal with a frustrating situation. Push the boat off! Wave bye!!!
There is no arriving, ever. It is all a continual becoming.