I agree that this is a really hard situation, especially when there are children involved. All I can say is do your reading, keep posting and look after yourself.
In my opinion all the work that you will put into yourself will help you either way. Maybe by saving your marriage, or if that is not possible it will equip you to deal with whatever is going to follow.
"There's nothing sadder than a conman conning himself"
“There is freedom waiting for you, On the breezes of the sky, And you ask "What if I fall?" Oh but my darling, What if you fly?”
