glad you didnt' feel insulted, it's amazing how much we still love them despite what happens. First, get yourself the book "love is tough" by J. Dobson.
Gradually go dark, he is way too confortable and maybe needs a jolt to actually realize: "hey, I'm going to loose her" to leave OW and straighten up.
If he asks why you are loosing touch w/him just tell him that it is too painful for you to go on this way and that you need time to think about the next step you need to make in your life. At the time I didnt' understand it, but that old cliche "if you want something let it go, if it comes back..." is so very true.
You and the kids deserve some stability, he is confortable thus he thinks you also must be, that this is a normal sitch. Well, it isn't and it's time he realizes he could loose his family if he doesn't make the rigth choice.
Be not afraid...I will repay you for the years the locusts have eaten Joel2
30something 2kids survivor of S, MLC, A, D I have peace in my heart, at last.