Now I find myself opening my mouth and telling myself "you already know the answer". "You don’t need to ask this again"
"This isn’t going to help you heal".
Ask a thousand times if you have to. It will help you heal and find the truth. Literally. You'll know when you're done asking and when you're at peace with the answer.
And you have every right. You go!
The heartbreak from "the incident" will never pass, but it is possible if the wrongs are named, to move past this.
"Then I find myself closing my mouth and not saying a damn thing because what is there to say?"
It's not clear from what you say, is it him who's closing your mouth because he's making you feel bad for asking? That you think you're harassing him by asking? Or have you come to the conclusion your conversation has truly come to an end? It sounds like you've given up being understood, either way, which happened to me too.
Again, ask him now. Talk. There won't be another time. Scream if you have to. Talk quietly when you have the energy and space. But don't give up yet if you know there is more space. Whatever decision you make will be based on the answers you get now, overt or subtle, no matter how long it takes, or what they are. Pay attention to the response and nuances from him. It's so hard I know.
I know you're exhausted. He caused all this and you have to do so much work to fix it. But please, lay the groundwork for a clear decision ... for yourself. No one else. Maybe he can be included. Only you will know that.
Move on into your future with as much clarity as you can find so you're free of doubt in your decisions.
Ask your questions a million more times. You have every right.
"seeing him happy makes me mad. I actually asked him how he can laugh and smile ... because I still have you and the kids ..."
Oh yeah! I remember that! Seeing him happy after made me so angry. He just wanted everything to get back to "normal".
Keep asking the questions.