Would you please provide some information about you and your h, i.e., ages, how long you have been married, children, etc.? It helps if we know a bit more about you and your situation.
Did something happen to your h in the last 18-24 months? Maybe a health issue, death of family member or co-worker, birth of a child, child going off to college, lost a job/promotion, started a new job, etc.
BTW, if your h is having an EA, he is cheating on you. The things that he's sharing w/the ow are things that he should be sharing w/you and you alone.
As for putting a clause in the separation agreement...I don't think it will fly. Your separation agree should be about finances, assets, the home, etc. Whether the clause is in there or not, you can't control what he does. The only person you can control is you and how you deal w/things happening in your life. My 2 cents is not to put that clause in there. Why? 1) it will anger him and draw out the process and that friendship you have w/him will go out the window and he'll become even more secretive; and/or 2)like a teenager/child, when you tell or ask them not to do something, they will most likely go out and do it just to spite you. The less you say about the ow, the better. She's nothing more than a Band-Aid to his woes right now.
Focus on what is important in getting the separation agreement in place. Make sure that the finances, etc., are split down the middle or very close to being fair and go from there. Keep the focus on you and leave your h in the hands of the man upstairs.
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.
