Alison gave you great psychological advice. From a practical standpoint, the anger must be vented somehow or you’ll start noticing worse physical effects than not sleeping or eating.
1. Talk to take the emotional edge off your anger. A parent or sister or friend can be a wonderful source of validation and reassurance. Do you think that you’re ready to start letting people in? Whether D or S is a foregone conclusion or not (and I think it is at their point) you need to start leaning on your trusted circle for support. Don’t worry about fear of judgment or what your H will say. This is for you.
2. Write down everything you are holding in. I know you already journal, but directing your thoughts with purpose could help with the anger. The notes app on your phone is handy. I drafted scathing letters to X that I never sent, Facebook posts exposing him and OW, a letter to his mother that I did eventually send, a list of boundaries I was struggling with at the time, canned responses to potential conversations... direct your anger somewhere rather than internalising it.
3. Lean into it by visualising everything that is causing you pain. This is really hard but the idea is to desensitise yourself. Imagine them having s-x. Imagine him kissing her and whispering that he loves her. Imagine them announcing their engagement or worse (I know he said he doesn’t want more kids but) a pregnancy. Imagine their wedding with your kids as flower girls. Imagine her as your kids step-mother. If you work through those feelings now, they won’t hurt as much later.
4. Act upon your anger. Generally I’d say he’s not worth the energy BUT you have to be authentic, so give yourself permission to throw some truth bombs if it’s what YOU need - not to try and change his behaviour. Just remember you have to be able to live with yourself and you don’t want any regrets when it comes to your kids. So be true to yourself. You don’t have to stuff your feelings down and you should never feel guilty for your anger when you have been victimised.
5. Buy a punching bag and boxing gloves. Put your H’s face on it if you want. Go to town. You might want to hide this from your kids if you put his face on it
