What is coming out of his mouth right now is from addiction, its not him talking.
You need to stop listening to what he's saying, its just a bunch of junk that's not worth analysing.
He's sounds like he's right in the heat of the addiction now. The last thing you want to do is push for a divorce.
Michele Davis reccomends waiting it out until reality of the affair sinks in... reality puts affairs to a painful death.
He's been in fantasy land until tonight when you told him. This was the first time his affair has seen the light of day and the addiction as expected got aggressive with you.
The more the affair is exposed to reality the less power it has and the quicker it ends.
Affair's don't last. Phil McGraw says according to his statistics affair couples have a LONG term success rate of less than 1%.
If you fight the affair long enough, you WILL win. You just need to be strong and decide if that's what you really want.
Do NOT take anything he says right now serioulsy. He is like an alcoholic right now and you tried to take his bottle away from him and he snapped at you. It will happen again until the affair takes more damage... Your confronting him did a LOT of damage and was a good thing.
Feed this affair as much reality as you can. He needs to know he won't have his kids available 24 x 7 anymore, he will heave to deal with finances and household maintenance, you won't care for him any longer, etc... all of this he is so used to right now he doens't realise it could go away.
Throw as much reality as you can at the two of them... It will slowly kill the addiction and your H will come back again.
That is when its best to decide if you want him or not... Don't judge him too harshly in the midst of an affair. He's addicted and he has little control over himself right now.
He will have to own this. He's not a victim, he invited the affair and he will be paying for it eventually one way or another.
But try to understand for both your sakes and for your kids that he's got an addiction right now and he's not in his right mind.