@Dudududodu you have bizarre ideas about how relationships are meant to work! No wonder you are so muddled.
Yea obviously your kids will be upset if the marriage ends. That's life. Change hurts. Are you aware that making decisions based on the metric "how can I make sure no one feels any emotions?" (and, I suspect, "how can I make sure I remain a victim so that no one will be angry with me?") is a road to utter disaster for your kids?
How do you think your kids are going to learn about courage OP?
Right now, you and your lovely husband are teaching them that love and life in general is about lying, manipulating, gaslighting and being faithless. And also about being utterly spineless, with a nice big dose of self-harm. That to be an adult means to return to the same shit, over and over, no matter how poisonous it is, like a dog returns to its vomit.
Look yourself in the eye and ask yourself why you're ok with this?
If your two choices for your marriage are both equally repellent to you - can I ask you why you wouldn't just go ahead with leaving him, since AT LEAST you would be doing right by your kids?
Where did you learn that the right way to raise kids is to shield them from every negative emotion, no matter what the cost to them long term? Because I'm very sorry but that is not love.
I see that you do the same to yourself... you can't tolerate your own emotions, are terrified of them, and so instead of just letting them happen, you run like a terrified child from them. No.matter the cost to you.
He will remarry, of course he will. You'll feel bad about it. Then you'll get over it. Surely you can see that?? A few months of feeling shit is completely survivable??? Why is it more important for you to avoid ever feeling sad, than it is for your children to learn the basics of how not to fuck their lives up? Really think about that OP..