He wants honesty, and yet when I ask for the same, he is sure to bring up the past and say you weren't honest with me. He thought he was best to hide it from me because he knew it would hurt me if he told me.
First - never assume what he is going to say. There is something on these boards about "Forget what you Know"....we can't assume that we know anything at this point in time.
Second - tell him that hiding things from each other (especially now) isn't helping anything.
If he throws the "you weren't honest with me" - my reaction would be to say "No, I wasn't...but now I've seen the type of damage hiding things can do." Not sure if this is a good response, since what I say always seems to backfire.