I would happily walk away and get a divorce if it wasn’t for the DC. They’re not old enough to understand splitting up but young enough to be hurt and confused.
OP, you've had enough posts telling you it ISN'T better for the children.
Well, I can prove it. I left my ex after 30 years, and I should have left far, far sooner. Both DCs have MH issues as a result of being around ex, and neither want a relationship with him.
He still send occasional emails trying to "prove" he loves me, but it's far too little, far too late. After all, words are cheap and actions speak much louder. Such as him paying up the child support he's not paying (CMS action in progress, he'll pay all right). He said it was because he wasn't seeing the DCs, refusing to see that their costs don't disappear just because he can't see them.
I did the walking on eggshells (although once he tried to gaslight me by claiming he was the one treading on eggshells around me, it didn't work).
We were subject to his moods and expectations, and the DC still mention how anxious I'd be to have the house tidy and clean before he got home from work, even though I worked FT as well.
I'd leave now, if I were you, OP. Don't bother waiting as a relaxed and calm parent will help your DCs settle into a new life.