The simple fact is that he is still lying about the OW. Until he starts respecting you and your M by telling the truth then you will never know where you stand. I know that it sucks but I am worried that he is going to hurt you again.
If I get a D (99.99% likely right now) the top three qualities that I will look for in my next relationship are
1. Honesty 2. Honesty 3. Honesty
The other stuff will be down the list. In my book it is all about respect.