“Go easy on yourself ^. So far, I think you’ve done an amazing job at prioritising the needs of your kids, protecting them from the worst of your ex and his nonsense and making practical choices that will benefit the futures of you and your DC. You’re absolutely allowed to feel sad, angry, confused, let down etc about a situation you didn’t create. Feel the feelings, have a good cry, then brush yourself off and crack on as you have been. The best gift you can give your kids is a Mummy who is happy and thriving, without an ex-shaped millstone manbaby around her neck.”^
@gillefc82 has nailed it. This with bells on.
As others have said, OP, the grief journey is a rollercoaster and it’s natural for you to have resurgences of pain and sadness around this situation - you have 4 children with this man who appeared to be all in with you and out of the blue, when you’re still on mat leave with 2 babies, announces that he’s leaving and it’s your fault because you’re controlling.
It’s not controlling to ask a fellow parent to step up and take shared responsibility for the family they have created. In any case, I will say that the more you describe him, the more it seems to me that he was the controlling one. He controlled you by going out at short notice for hours at a time meaning you had no option but to be home; he controlled you by refusing to let you discuss these matters with you and by making it so hard for you to go out that you ended up not bothering to do it.
He’s clearly an immature, selfish, spineless prick who won’t face his own wrongdoing, so I’m not suggesting you debate this with him, but from what i see he was the controlling one not you.
And to borrow a line from The Devil Wears Prada 2, you, @mummy917, are a Mumsnet icon!