You picked badly because you were lonely and wanted the family unit.
But it is far better to be alone than with the wrong man, and he sounds pretty awful.
Don't ignore the red flags in future, for your sake and your kids.
Losing a marriage is profoundly traumatic no matter how it happens. You just want to be loved and have what you are still grieving for - a normal family unit. You wanted to prove something to your ex, and you were lonely.
You picked badly first time out. Totally normal, and understandable.
You can learn from that, and fortunately can move on without any real hassles.
It's a very good thing for your kids you have finished with him.
In future please don't forget that the man you allow to have power over them - and he will have power over them no matter how careful you are - must be decent, sensible, stable, caring, even-tempered. Their lives will become a misery if their mother is ruled over by a shitty, controlling, boyfriend.
Even if you don't think you are worth a good, kind, decent, stable man I'm sure you think your kids have the right to being treated well.
And if you are ever unsure if a man's behaviour is acceptable or unacceptable, imagine your kids, all grown up and in relationships, and someone treating them as he is treating you. Because that's what you're modelling if you put up with men like him and bring men like him into their lives.
And if that's too far away to imagine, thnk of your best friend, sister, a woman you really love. Would you be ok with someone treating her the way he's treating you?
For your sake and for theirs, hold out for someone who treats you well, and if that means being alone, so be it. You deserve better, and so do they.