I'm sorry you're here, and I share your pain. My wife cheated on me, too, and it's the most painful thing that one can experience.
I read your other thread, and one thing occurs to me: have you ever tried to take him up on his offer of claiming to end all contact, by asking him to help set up a plan whereby you can feel he is following it? He wants to be "treated like an adult," well call him on that bluff (probably not today, but he'll try to come crawling back, trust me). When he does, say "OK, I am willing to work at this, and I don't want a divorce, but I absolutely refuse to have a third person in our marriage. You need to end it with her, and set up a plan whereby I know that you have, that is provable to me, in order for me to be able to rebuild trust with you." There are plans out there that do just that.
We see all types of wayward spouses on these boards. Some really don't care about their families, and others seem to TRY to be strong and come back to them, but are just weak and they relapse into the affair. Just based on the VERY brief info that you've given us in the two threads, your husband seems to me to possibly be the latter.
