Ugh. I had typed almost . My whole response when my phone died. Grrr.
I agree that you should communicate your rules and boundaries while you are still living in the same home.
Is it not possible for him to stay elsewhere in the meantime, for your sanity's sake?
I think you should avoid any communication with him that pertains to your emotions for the most part. He doesn't deserve it. However, I do think it is completely appropriate to relay to him how you see what he has done and the consequence trail he is leaving behind.
As a husband your expectations of him were that he would cherish you, protect you, support you through life's trials, be your best friend and confidant, your lover, the one who had your back when you needed it most, one who would grow with and change with you as you grew older, one who was committed to the vows you made at an altar before God, a co-parent who would love your children with you, nurture them, make memories that would last them a lifetime, show them by example what it is to be a man of integrity, a husband of integrity, a father of integrity, build them up to be strong, confident people who knew they were valued and loved, to show them how to have boundaries and goals, to prepare them to have relationships and marriages and be parents themselves someday.
Instead of cherishing you he abandoned you. Instead of protecting your heart he betrayed you. Instead of having your back he stabbed you in it. Instead of being your lover he gave himself to someone else. Instead of changing with you he pulled away from you. Instead if growing old with you he has ended your marriage and smashed your solemn vows on a selfish whim.
Instead of nurturing your children he is taking from them. He is stealing from them the opportunity to grow up with two parents in a bonded family and taking with him all of the memories they should have had growing up in an unbroken, supportive family; memories with their mom and dad together and the comfort that brings. Instead of showing them what it is to be a man, husband and father of integrity he has shown them what it is to cheat, lie, abandon, be selfish and choose himself over his family and inflict immense pain on his life partner and children. Instead of contributing to their confidence he has ripped away their foundation. Instead of showing them they are valued and loved he has demonstrated that his selfish desires come before their welfare and emotional well-being. Instead of teaching them how to have boundaries he has crossed every one and trampled those around him in his wake. Instead of living an example of how to manage healthy, loving, supportive marriage he has set them up for fear of intimacy, fear of being abandoned, fear to trust others promises, fear that they will never find a love that can stand the tests and trials that life brings. He has greatly increased the possibility of promiscuity, self loathing, self doubt and fear of rejection. Instead of learning by example what is is to be a parent of integrity, the lesson they will most likely adapt for themselves will hopefully be that they will promise themselves never to be like their dad so they won't hurt their own children.
This is his legacy. This is what he leaves behind to those he claimed to have loved. This is what his children will battle with for years to come.
I think if you gave him a taste of this it would be a healing step for you and a way to stick up for your children when they can't for themselves.
I also think that you should tell him that one of your requirements is that he sit down with the 'family' and be the one to explain to your children why your family will no longer be together and...if he refuses, that you will do it for him. The children deserve the truth (minus all the gory details).
Im so sorry. My heart breaks for you. I can't imagine having to co-exist in the same home with an active cheater while you prepare to divorce. Noone should have to deal with that. You are in my prayers and I'm here if you need to talk. (Dont know if you can pm yet?) Do you have friends or family you feel safe relying on for comfort and support?