The first real step of this process, I believe, is to get REAL with yourself and your situation -- to not "self-delude." You have done that IN SPADES. You obviously have a very sincere desire to learn, to grow, and to do whatever is necessary for yourself and your kids, and I admire the heck out of that.
I agree with just about everything you've gleaned from your weekend reading, and it's why I encouraged you to do it. Sometimes we get so caught up in the trees, that we can no longer see the forest clearly.
I do think there is some "trouble in paradise" caused by your mini-confrontation of the phone call, and it's why I'm so pro-exposure. Affairs are, at the core, built on deceit and fantasy, and confrontation and exposure bursts both of those twin bubbles.