I'm no good with relationships but I feel the serious need to tell you, if he lied about it... and then he confessed to you later on.... and it's because he was ashamed... he has most likely chanced since then, and he is ashamed because his moral values are diffrent than what they were back in his past...
but... being as you "hate him" ... it's better as to either work it out until you dont hate him, or to leave.... for if you hate him, and you have children with him, and then they grow up as you continue hatting him... they will have to survive you hating him, and fighting will probably happen very usual.
Everyone, correct me if i'm wrong anywhere in here please.. I dont wish to give bad advice.

But what i'm saying is don't subject your kids to that. They grow and usually want to be just like Mommy and Daddy... and in this instance they would maybe grow up hatting the world... that or totally going around and hating you and him (*from own experience there*) and vowing to never be that way...