Letting go is very difficult but you have to do it for yourself. You will feel SO much better. Trust me I struggled tremendously with letting go and detaching. I don't know if I ever fully did but when I appeared that way towards H it sure peaked his interest that I could be smiling and having fun (acting as if) while he was sure he was destroying my life with his behavior.
Letting go is for you. It's for your well being. Do you have any GAL activities that you are participating in? I found that my friends and family were very helpful in doing things and keeping busy that helped me. I personally did everything with my kids for the most part but had a few girls nights out. But for me my GAL usually always included my boys which was fine with me. However if your H is actively involved with your children on a regular basis (mine wasn't) then I would advocate for some GAL activities without the kids so that you aren't lost when they are with H
