Taylor, I also want to point out that it takes two to tango. If your h truly wanted this merry go round to cease, he would do it. Unfortunately the "high" of this affair is too much for him right now. Eventually when he realizes that you don't give a fig and it's now out in the light, it may begin to fizzle. Just as long as you keep attempting to bust it up, the more challenging it is for them to be together, be it by phone, email or in person.
Also, keep in mind, if it had not been this woman, it could have been another. They sometimes do not stop w/just one, it could be several. With what you know, have you been tested for STDs?
It is really important that you take care of yourself.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.